Nos Abonnements
Ressources Électroniques
|
[n° ou bulletin]
[n° ou bulletin]
Vol. 51 N° 2 - Janvier 2012 [texte imprimé] . - 2012 . - p. 605-1086 : ill. ; 28 cm. Chemical engineering Langues : Anglais (eng)
|
Exemplaires
| Code-barres | Cote | Support | Localisation | Section | Disponibilité |
|---|---|---|---|---|---|
| aucun exemplaire | |||||
|
Dépouillements
Ajouter le résultat dans votre panierThermodynamic properties of uranyl minerals / Tatiana Y. Shvareva in Industrial & engineering chemistry research, Vol. 51 N° 2 (Janvier 2012)
Titre : Thermodynamic properties of uranyl minerals : Constraints from calorimetry and solubility measurements Type de document : texte imprimé Auteurs : Tatiana Y. Shvareva, Auteur ; Jeremy B. Fein, Auteur ; Alexandria Navrotsky, Auteur Année de publication : 2012 Article en page(s) : pp. 607-613 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Solubility Calorimetry Thermodynamic properties Résumé : More than 50 uranyl minerals, phases containing U6+ as the uranyl UO22+ cation, and hydroxide, carbonate, phosphate, and silicate anions, H2O, and alkali and alkaline earth cations, occur in nature and as corrosion products of spent nuclear fuel. Despite their importance and the need to understand their thermodynamics to predict uranium solubility, fate, and transport in the environment, reliable thermodynamic data have only been available recently. This paper summarizes recent studies of enthalpies of formation using high temperature oxide melt solution calorimetry and Gibbs free energies from solubility experiments. Standud state thermochemical parameters (at 25 °C and I bar) are tabulated and the stability and transformation sequences of these phases are discussed. The enthalpies of formation from oxides are discussed in terms of crystal structure and Lewis acid-base interactions. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476390
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 607-613[article] Thermodynamic properties of uranyl minerals : Constraints from calorimetry and solubility measurements [texte imprimé] / Tatiana Y. Shvareva, Auteur ; Jeremy B. Fein, Auteur ; Alexandria Navrotsky, Auteur . - 2012 . - pp. 607-613.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 607-613
Mots-clés : Solubility Calorimetry Thermodynamic properties Résumé : More than 50 uranyl minerals, phases containing U6+ as the uranyl UO22+ cation, and hydroxide, carbonate, phosphate, and silicate anions, H2O, and alkali and alkaline earth cations, occur in nature and as corrosion products of spent nuclear fuel. Despite their importance and the need to understand their thermodynamics to predict uranium solubility, fate, and transport in the environment, reliable thermodynamic data have only been available recently. This paper summarizes recent studies of enthalpies of formation using high temperature oxide melt solution calorimetry and Gibbs free energies from solubility experiments. Standud state thermochemical parameters (at 25 °C and I bar) are tabulated and the stability and transformation sequences of these phases are discussed. The enthalpies of formation from oxides are discussed in terms of crystal structure and Lewis acid-base interactions. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476390 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Iodine confinement into metal – organic frameworks (MOFs) : Low - temperature sintering glasses to form novel glass composite material (GCM) alternative waste forms Type de document : texte imprimé Auteurs : Dorina F. Sava, Auteur ; Terry J. Garino, Auteur ; Tina M. Nenoff, Auteur Année de publication : 2012 Article en page(s) : pp.614–620 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Radioiodine Metal organic Résumé : The safe handling of reprocessed fuel addresses several scientific goals, especially when considering the capture and long-term storage of volatile radionuclides that are necessary during this process. Despite not being a major component of the off-gas, radioiodine (I2) is particularly challenging, because it is a highly mobile gas and 129I is a long-lived radionuclide (1.57 × 107 years). Therefore, its capture and sequestration is of great interest on a societal level. Herein, we explore novel routes toward the effective capture and storage of iodine. In particular, we report on the novel use of a new class of porous solid-state functional materials (metal–organic frameworks, MOFs), as high-capacity adsorbents of molecular iodine. We further describe the formation of novel glass-composite material (GCM) waste forms from the mixing and sintering of the I2-containing MOFs with Bi–Zn–O low-temperature sintering glasses and silver metal flakes. Our findings indicate that, upon sintering, a uniform monolith is formed, with no evidence of iodine loss; iodine is sequestered during the heating process by the in situ formation of AgI. Detailed materials characterization analysis is presented for the GCMs. This includes powder X-ray diffraction, scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM-EDS), thermal analysis (thermogravimetric analysis (TGA)), and chemical durability tests including aqueous leach studies (product consistency test (PCT)), with X-ray fluorescence (XRF) and inductively coupled plasma–mass spectrometry (ICP-MS) of the PCT leachate. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200248g?mi=snxuk8&af=R&pageSize=20&searchT [...]
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp.614–620[article] Iodine confinement into metal – organic frameworks (MOFs) : Low - temperature sintering glasses to form novel glass composite material (GCM) alternative waste forms [texte imprimé] / Dorina F. Sava, Auteur ; Terry J. Garino, Auteur ; Tina M. Nenoff, Auteur . - 2012 . - pp.614–620.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp.614–620
Mots-clés : Radioiodine Metal organic Résumé : The safe handling of reprocessed fuel addresses several scientific goals, especially when considering the capture and long-term storage of volatile radionuclides that are necessary during this process. Despite not being a major component of the off-gas, radioiodine (I2) is particularly challenging, because it is a highly mobile gas and 129I is a long-lived radionuclide (1.57 × 107 years). Therefore, its capture and sequestration is of great interest on a societal level. Herein, we explore novel routes toward the effective capture and storage of iodine. In particular, we report on the novel use of a new class of porous solid-state functional materials (metal–organic frameworks, MOFs), as high-capacity adsorbents of molecular iodine. We further describe the formation of novel glass-composite material (GCM) waste forms from the mixing and sintering of the I2-containing MOFs with Bi–Zn–O low-temperature sintering glasses and silver metal flakes. Our findings indicate that, upon sintering, a uniform monolith is formed, with no evidence of iodine loss; iodine is sequestered during the heating process by the in situ formation of AgI. Detailed materials characterization analysis is presented for the GCMs. This includes powder X-ray diffraction, scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM-EDS), thermal analysis (thermogravimetric analysis (TGA)), and chemical durability tests including aqueous leach studies (product consistency test (PCT)), with X-ray fluorescence (XRF) and inductively coupled plasma–mass spectrometry (ICP-MS) of the PCT leachate. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200248g?mi=snxuk8&af=R&pageSize=20&searchT [...] Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Defects and minor phases in O + and Zr + Ion Co - implanted SrTiO3 Type de document : texte imprimé Auteurs : Weilin Jiang, Auteur ; Mark E. Bowden, Auteur ; Zihua Zhu, Auteur Année de publication : 2012 Article en page(s) : pp. 621-628 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Defect Résumé : This article reports on a comprehensive experimental study of 16O+ and 90Zr+ ion co-implanted SrTiO3 (STO) single crystals. In this study, STO was used as a model material to simulate a waste form for disposal of radioactive 90Sr that decays to 90Y and subsequently to 90Zr by emission of β– particles. Sequential 16O+ and 90Zr+ ion implantation at 550 K was performed and Zr and O atomic concentrations of up to 1.5 atom % each in STO were achieved. A number of analytical methods were employed to characterize the implanted STO, including secondary-ion mass spectroscopy, multiaxial ion-channeling analysis, and high-resolution X-ray diffraction. The results show that a high defect concentration was generated and accumulated in STO during the ion implantation, but the crystal structure was not rendered fully amorphous. Thermal annealing at 1273 K leads to a significant defect recovery at the surface with little recovery occurring at the damage peak, where a modest recovery occurs upon further annealing at 1423 K. Some of the implanted Zr species are well aligned with the STO 001 axis, but nearly all are barely located at the substitutional sites due to structural distortion. A minor phase with a tetragonal structure is observed in the Zr distributed region, which has the 001 axis parallel to that of the STO host. The tetragonal phase survived annealing at 1423 K with only a small decrease in the c parameter. A general assessment of the model waste form is also provided in this report. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476392
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 621-628[article] Defects and minor phases in O + and Zr + Ion Co - implanted SrTiO3 [texte imprimé] / Weilin Jiang, Auteur ; Mark E. Bowden, Auteur ; Zihua Zhu, Auteur . - 2012 . - pp. 621-628.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 621-628
Mots-clés : Defect Résumé : This article reports on a comprehensive experimental study of 16O+ and 90Zr+ ion co-implanted SrTiO3 (STO) single crystals. In this study, STO was used as a model material to simulate a waste form for disposal of radioactive 90Sr that decays to 90Y and subsequently to 90Zr by emission of β– particles. Sequential 16O+ and 90Zr+ ion implantation at 550 K was performed and Zr and O atomic concentrations of up to 1.5 atom % each in STO were achieved. A number of analytical methods were employed to characterize the implanted STO, including secondary-ion mass spectroscopy, multiaxial ion-channeling analysis, and high-resolution X-ray diffraction. The results show that a high defect concentration was generated and accumulated in STO during the ion implantation, but the crystal structure was not rendered fully amorphous. Thermal annealing at 1273 K leads to a significant defect recovery at the surface with little recovery occurring at the damage peak, where a modest recovery occurs upon further annealing at 1423 K. Some of the implanted Zr species are well aligned with the STO 001 axis, but nearly all are barely located at the substitutional sites due to structural distortion. A minor phase with a tetragonal structure is observed in the Zr distributed region, which has the 001 axis parallel to that of the STO host. The tetragonal phase survived annealing at 1423 K with only a small decrease in the c parameter. A general assessment of the model waste form is also provided in this report. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476392 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Alternatives to HDEHP and DTPA for simplified TALSPEAK separations Type de document : texte imprimé Auteurs : Jenifer C. Braley, Auteur ; Travis S. Grimes, Auteur ; Kenneth L. Nash, Auteur Année de publication : 2012 Article en page(s) : pp. 629-638 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Talspeak process Résumé : The TALSPEAK process is an established option for lanthanide/minor actinide separations using solvent extraction. In this process, selective extraction of lanthanides is achieved by contacting a water-soluble aminopolycarboxylate complexant in a concentrated carboxylic acid buffer with a liquid cation exchanging extractant in an immiscible organic diluent. Although TALSPEAK process development has been successful on several levels, studies of the detailed fundamental chemistry have revealed undesirable complex interactions between aqueous and organic solute species. These complications threaten to impair process modeling and could impact engineered operations. In the present work, results are reported describing equilibrium partitioning and phase transfer kinetics trends for trivalent lanthanide ions and americium into bis-2-ethyl(hexyl) phosphoric acid (HDEHP) or structural analog 2-ethyl(hexyl) phosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) organic phases from aqueous lactate solutions containing diethylenetriamine-N,N,N′,N′′,N′′-pentaacetic acid (DTPA), triethylenetetramine-N,N,N′,N′′,N′′′,N′′′-hexaacetic acid (TTHA), or N-(2-hydroxyethyl)ethylenediamine-N,N′,N′-triacetic acid (HEDTA). The undesirable partitioning of Na+, lactic acid, and water into the organic phase is greatly reduced when HEH[EHP] replaces HDEHP as the extractant. TTHA appears to offer little advantage over DTPA in conventional TALSPEAK, but both DTPA and TTHA are too strong for use in combination with HEH[EHP]. The combination of HEDTA with HEH[EHP] achieves good balance and exhibits a nearly flat pH dependence between 2.5 and 4.5, in contrast with conventional TALSPEAK. The latter combination demonstrates more predictable performance than is seen in conventional TALSPEAK, while providing acceptable americium/lanthanide separation factors. The HEDTA/HEH[EHP] combination offers the additional advantage of more rapid phase transfer kinetics for the heavier lanthanides without the need for high concentrations of a lactate buffer. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200285r
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 629-638[article] Alternatives to HDEHP and DTPA for simplified TALSPEAK separations [texte imprimé] / Jenifer C. Braley, Auteur ; Travis S. Grimes, Auteur ; Kenneth L. Nash, Auteur . - 2012 . - pp. 629-638.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 629-638
Mots-clés : Talspeak process Résumé : The TALSPEAK process is an established option for lanthanide/minor actinide separations using solvent extraction. In this process, selective extraction of lanthanides is achieved by contacting a water-soluble aminopolycarboxylate complexant in a concentrated carboxylic acid buffer with a liquid cation exchanging extractant in an immiscible organic diluent. Although TALSPEAK process development has been successful on several levels, studies of the detailed fundamental chemistry have revealed undesirable complex interactions between aqueous and organic solute species. These complications threaten to impair process modeling and could impact engineered operations. In the present work, results are reported describing equilibrium partitioning and phase transfer kinetics trends for trivalent lanthanide ions and americium into bis-2-ethyl(hexyl) phosphoric acid (HDEHP) or structural analog 2-ethyl(hexyl) phosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) organic phases from aqueous lactate solutions containing diethylenetriamine-N,N,N′,N′′,N′′-pentaacetic acid (DTPA), triethylenetetramine-N,N,N′,N′′,N′′′,N′′′-hexaacetic acid (TTHA), or N-(2-hydroxyethyl)ethylenediamine-N,N′,N′-triacetic acid (HEDTA). The undesirable partitioning of Na+, lactic acid, and water into the organic phase is greatly reduced when HEH[EHP] replaces HDEHP as the extractant. TTHA appears to offer little advantage over DTPA in conventional TALSPEAK, but both DTPA and TTHA are too strong for use in combination with HEH[EHP]. The combination of HEDTA with HEH[EHP] achieves good balance and exhibits a nearly flat pH dependence between 2.5 and 4.5, in contrast with conventional TALSPEAK. The latter combination demonstrates more predictable performance than is seen in conventional TALSPEAK, while providing acceptable americium/lanthanide separation factors. The HEDTA/HEH[EHP] combination offers the additional advantage of more rapid phase transfer kinetics for the heavier lanthanides without the need for high concentrations of a lactate buffer. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200285r Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Synthesis of nano calcium oxide from a gastropod shell and the performance evaluation for Cr (VI) removal from aqua system Type de document : texte imprimé Auteurs : N. A. Oladoja, Auteur ; I. A. Ololade, Auteur ; S.E. Olaseni, Auteur Année de publication : 2012 Article en page(s) : pp. 639-648 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Porous nano Calcium oxide Résumé : A spongy, porous nano calcium oxide (NC) with point zero charge of 11.80 was synthesized using the shell of a Gastropod (Achatina achatina) via the sol–gel technique. The ability of the NC to adsorb Cr (VI) from aqueous solution was assessed systematically in a batch process via isothermal, kinetic, and variable process optimization procedure. The sorption data had the best fitting for the Langmuir isotherm model and the monolayer sorption capacity (qm, mg/g) value of 125 mg/g was obtained. The initial solution pH had no palpable effect on the monolayer sorption capacity. The amount of sorbed Cr (VI) increased with contact time and initial Cr (VI) concentration and attained equilibrium within 120 min. The fitting of the different kinetic models to the sorption data, by error analysis, using the linear coefficient determinations (r2) and the Chi-square statistical analysis (χ2), showed that the mechanism of the sorption process is better described by the pseudo second order kinetic model. Thermodynamic evaluation showed that the sorption process was spontaneous (ΔGo: −15.27; −14.87 and −14.45 kJ/mol at 303, 313, and 333 °C, respectively), exothermic (ΔH0 = −22.568 kJ/mol) and increased disorder (ΔS0 = 0.0244) appeared on the NC–solution interface during the adsorption process. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201189z
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 639-648[article] Synthesis of nano calcium oxide from a gastropod shell and the performance evaluation for Cr (VI) removal from aqua system [texte imprimé] / N. A. Oladoja, Auteur ; I. A. Ololade, Auteur ; S.E. Olaseni, Auteur . - 2012 . - pp. 639-648.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 639-648
Mots-clés : Porous nano Calcium oxide Résumé : A spongy, porous nano calcium oxide (NC) with point zero charge of 11.80 was synthesized using the shell of a Gastropod (Achatina achatina) via the sol–gel technique. The ability of the NC to adsorb Cr (VI) from aqueous solution was assessed systematically in a batch process via isothermal, kinetic, and variable process optimization procedure. The sorption data had the best fitting for the Langmuir isotherm model and the monolayer sorption capacity (qm, mg/g) value of 125 mg/g was obtained. The initial solution pH had no palpable effect on the monolayer sorption capacity. The amount of sorbed Cr (VI) increased with contact time and initial Cr (VI) concentration and attained equilibrium within 120 min. The fitting of the different kinetic models to the sorption data, by error analysis, using the linear coefficient determinations (r2) and the Chi-square statistical analysis (χ2), showed that the mechanism of the sorption process is better described by the pseudo second order kinetic model. Thermodynamic evaluation showed that the sorption process was spontaneous (ΔGo: −15.27; −14.87 and −14.45 kJ/mol at 303, 313, and 333 °C, respectively), exothermic (ΔH0 = −22.568 kJ/mol) and increased disorder (ΔS0 = 0.0244) appeared on the NC–solution interface during the adsorption process. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201189z Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Use of gas diffusion electrode for the in situ generation of hydrogen peroxide in an electrochemical flow - by reactor Type de document : texte imprimé Auteurs : Rafael M. Reis, Auteur ; André A. G. F. Beati, Auteur ; Robson S. Rocha, Auteur Année de publication : 2012 Article en page(s) : pp. 649-654 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Reactor Hydrogen production In situ Electrodes Gaseous diffusion Résumé : Hydrogen peroxide is a powerful oxidant that finds application in several areas, but most particularly in the treatment of industrial wastewaters. The aim of the present study was to investigate the effects of applied potential and electrolyte flow conditions on the in situ generation of hydrogen peroxide in an electrochemical flow-by reactor with a gas diffusion electrode (GDE). The electrolyses were performed in an aqueous acidic medium using a GDE constructed with conductive black graphite and polytetrafluoroethylene (80:20 w/w). Under laminar flow conditions (flow rate = 50 L/h), hydrogen peroxide was formed in a maximum yield of414mg/L after 2 h at -2.25 Vvs Pt //Ag/AgCl (global rate constant = 3.1 mg/(L min); energy consumption = 22.1 kWh/kg). Under turbulent flow (300 L/h), the maximum yield obtained was 294 mg/L after 2 h at -1.75 V vs Pt//Ag/AgCl (global rate constant = 2.5 mg/(L min); energy consumption =30.1 kWh/kg). DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476395
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 649-654[article] Use of gas diffusion electrode for the in situ generation of hydrogen peroxide in an electrochemical flow - by reactor [texte imprimé] / Rafael M. Reis, Auteur ; André A. G. F. Beati, Auteur ; Robson S. Rocha, Auteur . - 2012 . - pp. 649-654.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 649-654
Mots-clés : Reactor Hydrogen production In situ Electrodes Gaseous diffusion Résumé : Hydrogen peroxide is a powerful oxidant that finds application in several areas, but most particularly in the treatment of industrial wastewaters. The aim of the present study was to investigate the effects of applied potential and electrolyte flow conditions on the in situ generation of hydrogen peroxide in an electrochemical flow-by reactor with a gas diffusion electrode (GDE). The electrolyses were performed in an aqueous acidic medium using a GDE constructed with conductive black graphite and polytetrafluoroethylene (80:20 w/w). Under laminar flow conditions (flow rate = 50 L/h), hydrogen peroxide was formed in a maximum yield of414mg/L after 2 h at -2.25 Vvs Pt //Ag/AgCl (global rate constant = 3.1 mg/(L min); energy consumption = 22.1 kWh/kg). Under turbulent flow (300 L/h), the maximum yield obtained was 294 mg/L after 2 h at -1.75 V vs Pt//Ag/AgCl (global rate constant = 2.5 mg/(L min); energy consumption =30.1 kWh/kg). DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476395 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Methylation of glycerol with dimethyl sulfate to produce a new oxygenate additive for diesels Type de document : texte imprimé Auteurs : Jyh-Shyong Chang, Auteur ; Yu-Da Lee, Auteur ; Lawrence Chao-Shan Chou, Auteur Année de publication : 2012 Article en page(s) : pp. 655-661 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Additive Methylation Résumé : A new oxygenate additive for diesels (bio or petroleum) was manufactured using glycerol, dimethyl sulfate (DMS), and sodium hydroxide pellets as raw materials. By feeding the dimethyl sulfate into the batch reactor containing the sodium glycerate, a semibatch mode operation enhanced the effective methylation of glycerol. A conventional stirred tank reactor that can produce large quantities of oxygenate additives under a normal atmospheric pressure operation became the main feature of the methylation process. With a 3:2 molar ratio of DMS to glycerol, a 3:1 molar ratio of sodium hydroxide to glycerol, a 0.43:1 molar ratio of water to sodium hydroxide, and a temperature of 343 K at the reaction time of 24 h with the feeding time ofDMS under 12 h, the conversion of glycerol (93.5%) and a combined yield of GDMEs and GTME of 71.2% were achieved for a once-through operation. A product mixture of GDME (20 wt %) and GTME (80 wt %) served as a new oxygenate additive for (bio or petroleum) diesels. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476396
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 655-661[article] Methylation of glycerol with dimethyl sulfate to produce a new oxygenate additive for diesels [texte imprimé] / Jyh-Shyong Chang, Auteur ; Yu-Da Lee, Auteur ; Lawrence Chao-Shan Chou, Auteur . - 2012 . - pp. 655-661.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 655-661
Mots-clés : Additive Methylation Résumé : A new oxygenate additive for diesels (bio or petroleum) was manufactured using glycerol, dimethyl sulfate (DMS), and sodium hydroxide pellets as raw materials. By feeding the dimethyl sulfate into the batch reactor containing the sodium glycerate, a semibatch mode operation enhanced the effective methylation of glycerol. A conventional stirred tank reactor that can produce large quantities of oxygenate additives under a normal atmospheric pressure operation became the main feature of the methylation process. With a 3:2 molar ratio of DMS to glycerol, a 3:1 molar ratio of sodium hydroxide to glycerol, a 0.43:1 molar ratio of water to sodium hydroxide, and a temperature of 343 K at the reaction time of 24 h with the feeding time ofDMS under 12 h, the conversion of glycerol (93.5%) and a combined yield of GDMEs and GTME of 71.2% were achieved for a once-through operation. A product mixture of GDME (20 wt %) and GTME (80 wt %) served as a new oxygenate additive for (bio or petroleum) diesels. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476396 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Lime treatment of prehydrolysis liquor from the kraft - based dissolving pulp production process Type de document : texte imprimé Auteurs : Jing Shen, Auteur ; Pedram Fatehi, Auteur ; Pendar Soleimani, Auteur Année de publication : 2012 Article en page(s) : pp. 662–667 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Prehydrolysis liquor Résumé : In this study, the concept of using lime for the treatment of industrially produced prehydrolysis liquor (PHL) of kraft-based dissolving pulp production process was tested, and its effect on the concentrations of acetic acid, furfural, UV lignin, and hemicelluloses was explored. Lime treatment resulted in a significant increase in the acetic acid concentration due to alkaline hydrolysis of the acetyl groups bound to the dissolved hemicelluloses in PHL, and the degradation of sugars. At relatively high lime dosages (e.g., above 1.7%), furfural was completely eliminated, while the lignin concentration decreased by 20–25%. The hemicelluloses concentration can be significantly decreased due to the alkaline oxidative degradation. However, when performed in the absence of oxygen/air by bubbling carbon dioxide to the lime/PHL system, the degradation of hemicelluloses was effectively minimized. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2019195
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 662–667[article] Lime treatment of prehydrolysis liquor from the kraft - based dissolving pulp production process [texte imprimé] / Jing Shen, Auteur ; Pedram Fatehi, Auteur ; Pendar Soleimani, Auteur . - 2012 . - pp. 662–667.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 662–667
Mots-clés : Prehydrolysis liquor Résumé : In this study, the concept of using lime for the treatment of industrially produced prehydrolysis liquor (PHL) of kraft-based dissolving pulp production process was tested, and its effect on the concentrations of acetic acid, furfural, UV lignin, and hemicelluloses was explored. Lime treatment resulted in a significant increase in the acetic acid concentration due to alkaline hydrolysis of the acetyl groups bound to the dissolved hemicelluloses in PHL, and the degradation of sugars. At relatively high lime dosages (e.g., above 1.7%), furfural was completely eliminated, while the lignin concentration decreased by 20–25%. The hemicelluloses concentration can be significantly decreased due to the alkaline oxidative degradation. However, when performed in the absence of oxygen/air by bubbling carbon dioxide to the lime/PHL system, the degradation of hemicelluloses was effectively minimized. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2019195 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Corrosion inhibition and adsorption behavior of punica granatum extract on mild steel in acidic environments : Experimental and theoretical studies Type de document : texte imprimé Auteurs : Maduabuchi A. Chidiebere, Auteur ; Cynthia E. Ogukwe, Auteur ; Kanayo L. Oguzie, Auteur Année de publication : 2012 Article en page(s) : pp. 668-677 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Mild steel Extract Adsorption Corrosion inhibition Résumé : The adsorption and corrosion inhibiting effect of aqueous extracts of Punica granatum (PNG) on mild steel in 1 M HCl and 0.5 M H2SO4 at 30 ± 1 °C was investigated using gravimetric, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization techniques. The experimental findings revealed that PNG inhibited the corrosion reaction in both acid environments. Impedance results indicate that the extract organic matter was adsorbed on the metal/solution interface, while polarization data show that the extract behaved mostly as a mixed-type inhibitor. A theoretical study of the adsorption behavior of some of the components of the crude extracts was carried out in the framework of the density functional theory (DFT). DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476398
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 668-677[article] Corrosion inhibition and adsorption behavior of punica granatum extract on mild steel in acidic environments : Experimental and theoretical studies [texte imprimé] / Maduabuchi A. Chidiebere, Auteur ; Cynthia E. Ogukwe, Auteur ; Kanayo L. Oguzie, Auteur . - 2012 . - pp. 668-677.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 668-677
Mots-clés : Mild steel Extract Adsorption Corrosion inhibition Résumé : The adsorption and corrosion inhibiting effect of aqueous extracts of Punica granatum (PNG) on mild steel in 1 M HCl and 0.5 M H2SO4 at 30 ± 1 °C was investigated using gravimetric, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization techniques. The experimental findings revealed that PNG inhibited the corrosion reaction in both acid environments. Impedance results indicate that the extract organic matter was adsorbed on the metal/solution interface, while polarization data show that the extract behaved mostly as a mixed-type inhibitor. A theoretical study of the adsorption behavior of some of the components of the crude extracts was carried out in the framework of the density functional theory (DFT). DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476398 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Reactions of sodium peroxide with components of legacy plutonium materials Type de document : texte imprimé Auteurs : Robert A. Pierce, Auteur ; Dario C. Castiglione, Auteur ; David M. Missimer, Auteur Année de publication : 2012 Article en page(s) : pp. 678-681 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Plutonium oxide Résumé : Plutonium oxide (PuO2) calcined at >900 °C resists dissolution in nitric acid (HNO3)-potassium fluoride (KF) solutions commonly used for their dissolution. The Savannah River National Laboratory (SRNL) has developed an alternate method for large samples of PuO2-bearing materials using sodium peroxide (Na2O2) fusion as a pretreatment. The products of the reaction between Na2O2 and PuO2 have been reported in the literature. As part of the SRNL development effort, additional data about the reaction between Na2O2 and PuO2 were required. Also needed were data concerning the reaction of Na2O2 with other components that may be present in the feed materials. Sodium peroxide was reacted with aluminum metal (Al), beryllium metal (Be), graphite, potassium chloride (KCl), magnesium chloride (MgCl2), and calcium chloride (CaCl2). The paper reports and discusses the reaction products of these and related compounds with Na2O2. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202277m
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 678-681[article] Reactions of sodium peroxide with components of legacy plutonium materials [texte imprimé] / Robert A. Pierce, Auteur ; Dario C. Castiglione, Auteur ; David M. Missimer, Auteur . - 2012 . - pp. 678-681.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 678-681
Mots-clés : Plutonium oxide Résumé : Plutonium oxide (PuO2) calcined at >900 °C resists dissolution in nitric acid (HNO3)-potassium fluoride (KF) solutions commonly used for their dissolution. The Savannah River National Laboratory (SRNL) has developed an alternate method for large samples of PuO2-bearing materials using sodium peroxide (Na2O2) fusion as a pretreatment. The products of the reaction between Na2O2 and PuO2 have been reported in the literature. As part of the SRNL development effort, additional data about the reaction between Na2O2 and PuO2 were required. Also needed were data concerning the reaction of Na2O2 with other components that may be present in the feed materials. Sodium peroxide was reacted with aluminum metal (Al), beryllium metal (Be), graphite, potassium chloride (KCl), magnesium chloride (MgCl2), and calcium chloride (CaCl2). The paper reports and discusses the reaction products of these and related compounds with Na2O2. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202277m Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Simulation and analysis of an ethylene slurry polymerization system using supercritical propane Type de document : texte imprimé Auteurs : Zhao Xiaojun, Auteur ; Guo Xiaojun, Auteur ; Cheng Peng, Auteur Année de publication : 2012 Article en page(s) : pp. 682-690 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Supercritical state Polymerization Résumé : In this paper, a model for an ethylene slurry polymerization system using supercritical propane as a solvent is developed by adopting a set of thermodynamic and kinetic parameters using fundamental chemical engineering principles and Polymers Plus software. The Ziegler-Natta catalyst is characterized by assuming the existence of multiple types of catalyst sites and deconvolution data from gel permeation chromatography to determine the most probable chain-length distribution and relative amounts of polymer produced at each site type. A set of suitable reaction subclasses and kinetic constants for different site types that fit plant conditions is developed, validating our model. The values calculated for production rate, ethylene conversion, residence time, H2/C2H4 molar ratio in the reactor, number-average molecular weight, and polydispersity index are all close to actual values, verifying that our model accurately describes plant conditions. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476400
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 682-690[article] Simulation and analysis of an ethylene slurry polymerization system using supercritical propane [texte imprimé] / Zhao Xiaojun, Auteur ; Guo Xiaojun, Auteur ; Cheng Peng, Auteur . - 2012 . - pp. 682-690.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 682-690
Mots-clés : Supercritical state Polymerization Résumé : In this paper, a model for an ethylene slurry polymerization system using supercritical propane as a solvent is developed by adopting a set of thermodynamic and kinetic parameters using fundamental chemical engineering principles and Polymers Plus software. The Ziegler-Natta catalyst is characterized by assuming the existence of multiple types of catalyst sites and deconvolution data from gel permeation chromatography to determine the most probable chain-length distribution and relative amounts of polymer produced at each site type. A set of suitable reaction subclasses and kinetic constants for different site types that fit plant conditions is developed, validating our model. The values calculated for production rate, ethylene conversion, residence time, H2/C2H4 molar ratio in the reactor, number-average molecular weight, and polydispersity index are all close to actual values, verifying that our model accurately describes plant conditions. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476400 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : MathematicalModeling of air – and oxy – coal confined swirling flames on two extended eddy - dissipation models Type de document : texte imprimé Auteurs : Jingzhang Liu, Auteur ; Sheng Chen, Auteur ; Zhaohui Liu, Auteur Année de publication : 2012 Article en page(s) : pp. 691-703 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Flame Vortex Coal Modeling Résumé : The mathematical modeling of air― and oxy―coal flames is a great challenge because of the complexity of the turbulence chemistry interactions. However, the different turbulence chemistry interaction models can give very different results. Therefore, an investigation of the effects of these interactions on air― and oay―coal flames is needed, especially with both improved kinetic mechanisms and modified physical parameters. This work presents a numerical investigation of the effects of the interaction models on the characteristics of air― and oxy―coal confined swirling flames. These interaction models are two extended eddy- dissipation models (EDMs), the finite-rate and eddy-dissipation (FRED) model and the eddy dissipation concept (EDC) model. First, two important factors were considered in the oxy―coal combustion simulations, namely, improved global reaction mechanisms and modified physical parameters. Second, with these improvements and modifications, numerical simulations of air― and oxy―coal flames were carried out. The results showed that the flames focus on the horizontal center and propagate forward with a swirling closure shape and that the flame shapes belong to an intensively accelerated flame type IL. Good predictions of the combustion efficiencies were obtained by these two combustion models. Superior predictions of both the exhausted flue gas mixture and the minor carbon monoxide concentration were obtained with the eddy dissipation-chemical equilibrium (EDC) model. However, both ignition delays and temperature fields were better predicted with the kinetic-controlled and mixed-is-burned (FRED) model. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476401
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 691-703[article] MathematicalModeling of air – and oxy – coal confined swirling flames on two extended eddy - dissipation models [texte imprimé] / Jingzhang Liu, Auteur ; Sheng Chen, Auteur ; Zhaohui Liu, Auteur . - 2012 . - pp. 691-703.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 691-703
Mots-clés : Flame Vortex Coal Modeling Résumé : The mathematical modeling of air― and oxy―coal flames is a great challenge because of the complexity of the turbulence chemistry interactions. However, the different turbulence chemistry interaction models can give very different results. Therefore, an investigation of the effects of these interactions on air― and oay―coal flames is needed, especially with both improved kinetic mechanisms and modified physical parameters. This work presents a numerical investigation of the effects of the interaction models on the characteristics of air― and oxy―coal confined swirling flames. These interaction models are two extended eddy- dissipation models (EDMs), the finite-rate and eddy-dissipation (FRED) model and the eddy dissipation concept (EDC) model. First, two important factors were considered in the oxy―coal combustion simulations, namely, improved global reaction mechanisms and modified physical parameters. Second, with these improvements and modifications, numerical simulations of air― and oxy―coal flames were carried out. The results showed that the flames focus on the horizontal center and propagate forward with a swirling closure shape and that the flame shapes belong to an intensively accelerated flame type IL. Good predictions of the combustion efficiencies were obtained by these two combustion models. Superior predictions of both the exhausted flue gas mixture and the minor carbon monoxide concentration were obtained with the eddy dissipation-chemical equilibrium (EDC) model. However, both ignition delays and temperature fields were better predicted with the kinetic-controlled and mixed-is-burned (FRED) model. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476401 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Enhanced and selective degradation of pollutants over cyclodextrin / TiO2 under visible light irradiation Type de document : texte imprimé Auteurs : Xu Zhang, Auteur ; Xuankun Li, Auteur ; Nansheng Deng, Auteur Année de publication : 2012 Article en page(s) : pp. 704-709 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Visible radiation Titanium oxide Pollutant Résumé : The photocatalytic performance of cydodextrin modified TiO2 (TiO2/β-CD) on the degradation of rhodamine B and bisphenol A (BPA) was studied in this work. The interactions between β-CD and TiO2 varied as the synthesis method changes. When applying TiO2/β-CD synthesized from photoinduced self-assembly method as photocatalyst, the initial visible light (λ ≥ 420 nm) degradation rates R0 of rhodamine B and BPA increased by 4.6 and 3.2 times respectively. The TiO2/β-CD hybrid material synthesized from adsorption method only showed enhancement in dye pollutants degradation. The reactivity of TiO2/β-CD under visible light was correlated with the specific surface area of unmodified semiconductor. The mechanism for the enhanced and selective degradation of pollutants over TiO2/β-CD was also proposed in this work. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476402
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 704-709[article] Enhanced and selective degradation of pollutants over cyclodextrin / TiO2 under visible light irradiation [texte imprimé] / Xu Zhang, Auteur ; Xuankun Li, Auteur ; Nansheng Deng, Auteur . - 2012 . - pp. 704-709.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 704-709
Mots-clés : Visible radiation Titanium oxide Pollutant Résumé : The photocatalytic performance of cydodextrin modified TiO2 (TiO2/β-CD) on the degradation of rhodamine B and bisphenol A (BPA) was studied in this work. The interactions between β-CD and TiO2 varied as the synthesis method changes. When applying TiO2/β-CD synthesized from photoinduced self-assembly method as photocatalyst, the initial visible light (λ ≥ 420 nm) degradation rates R0 of rhodamine B and BPA increased by 4.6 and 3.2 times respectively. The TiO2/β-CD hybrid material synthesized from adsorption method only showed enhancement in dye pollutants degradation. The reactivity of TiO2/β-CD under visible light was correlated with the specific surface area of unmodified semiconductor. The mechanism for the enhanced and selective degradation of pollutants over TiO2/β-CD was also proposed in this work. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476402 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Kinetic study of methanol synthesis over CuO / ZnO / Al2O3 / V2O3 catalyst deposited on a stainless steel surface Type de document : texte imprimé Auteurs : David Perko, Auteur ; Janez Levec, Auteur Année de publication : 2012 Article en page(s) : pp. 710-718 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Stainless steel Catalyst Kinetics Résumé : A spraying method for coating stainless steel surfaces with a commercial methanol synthesis catalyst was studied for the purpose of making a thin, active, and durable plate catalyst. The catalyst slurry was composed of CuO/ZnO/Al2O3/V2O3 powder dispersed in 2-propanol and was sprayed on a curved stainless steel surface. The coating was found to exhibit good adhesion to the metal surface and to provide a considerable increase in surface area relative to the geometrical area of the metal support surface (up to a factor of 11000). The effects of key method parameters, namely, the size of the catalyst particles in the suspension and the coating thickness, on the efficiency of coating and the morphology and durability of the coating were briefly investigated. The intrinsic kinetics of carbon dioxide and carbon monoxide hydrogenation, as well as the WGS reaction, on the prepared plate catalyst were evaluated and compared to literature data. The reactions were carried out in a continuous stirred-tank reactor (CSTR) system appropriately assembled with a curved plate catalyst in the absence of mass-transfer limitations. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476403
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 710-718[article] Kinetic study of methanol synthesis over CuO / ZnO / Al2O3 / V2O3 catalyst deposited on a stainless steel surface [texte imprimé] / David Perko, Auteur ; Janez Levec, Auteur . - 2012 . - pp. 710-718.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 710-718
Mots-clés : Stainless steel Catalyst Kinetics Résumé : A spraying method for coating stainless steel surfaces with a commercial methanol synthesis catalyst was studied for the purpose of making a thin, active, and durable plate catalyst. The catalyst slurry was composed of CuO/ZnO/Al2O3/V2O3 powder dispersed in 2-propanol and was sprayed on a curved stainless steel surface. The coating was found to exhibit good adhesion to the metal surface and to provide a considerable increase in surface area relative to the geometrical area of the metal support surface (up to a factor of 11000). The effects of key method parameters, namely, the size of the catalyst particles in the suspension and the coating thickness, on the efficiency of coating and the morphology and durability of the coating were briefly investigated. The intrinsic kinetics of carbon dioxide and carbon monoxide hydrogenation, as well as the WGS reaction, on the prepared plate catalyst were evaluated and compared to literature data. The reactions were carried out in a continuous stirred-tank reactor (CSTR) system appropriately assembled with a curved plate catalyst in the absence of mass-transfer limitations. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476403 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Effect of macropore formation in Pt catalyst supports on the oxidation activity for diesel fuel mist Type de document : texte imprimé Auteurs : Junko Uchisawa, Auteur ; Akira Obuchi, Auteur ; Tetsuya Nanba, Auteur Année de publication : 2012 Article en page(s) : pp. 719-724 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Diesel fuel Oxidation Catalyst support Macroporosity Résumé : The effect of macropore formation in catalyst supports on the oxidation activity for diesel fuel mist was examined with the goal of improving catalyst efficiency. To investigate the effect on a laboratory scale using granular samples, we designed a reaction system that supplied fuel mist to the catalyst bed directly by an air atomizing nozzle. The catalytic activity was found to be improved by macropore formation in the support. This effect was also demonstrated for a washcoated catalyst on a honeycomb with diesel engine exhaust. These results suggest that the macropore diffusion channels are secure even if fuel mist attaches to the support surface, and the reactant gas can diffuse to the interior of the support and reach the active sites. Macropore formation prevented the blockage of pores of the support surface and thus the active sites of the catalyst. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476404
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 719-724[article] Effect of macropore formation in Pt catalyst supports on the oxidation activity for diesel fuel mist [texte imprimé] / Junko Uchisawa, Auteur ; Akira Obuchi, Auteur ; Tetsuya Nanba, Auteur . - 2012 . - pp. 719-724.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 719-724
Mots-clés : Diesel fuel Oxidation Catalyst support Macroporosity Résumé : The effect of macropore formation in catalyst supports on the oxidation activity for diesel fuel mist was examined with the goal of improving catalyst efficiency. To investigate the effect on a laboratory scale using granular samples, we designed a reaction system that supplied fuel mist to the catalyst bed directly by an air atomizing nozzle. The catalytic activity was found to be improved by macropore formation in the support. This effect was also demonstrated for a washcoated catalyst on a honeycomb with diesel engine exhaust. These results suggest that the macropore diffusion channels are secure even if fuel mist attaches to the support surface, and the reactant gas can diffuse to the interior of the support and reach the active sites. Macropore formation prevented the blockage of pores of the support surface and thus the active sites of the catalyst. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476404 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : High photocatalytic activity of magnetically separable manganese ferrite – graphene heteroarchitectures Type de document : texte imprimé Auteurs : Yongsheng Fu, Auteur ; Pan Xiong, Auteur ; Haiqun Chen, Auteur Année de publication : 2012 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Photocatalysis Résumé : A simple and straightforward strategy was developed to fabricate magnetically separable MnFe2O4―grapbene photocatalysts with differing graphene content. It was found that graphene sheets were fully exfoliated and decorated with MnFe2O4 nanocrystals having an average diameter of 5.65 nm and a narrow particle size distribution. It is very interesting that, although MnFe2O4 alone is photocatalytically inactive under visible light irradiation, the combination of MnFe2O4 nanoparticles with gaphene sheets leads to high photocatalytic activity for the degradation ofmethylene blue under visible light irradiation. The strong magnetic property of MnFe2O4 nanoparticles can be used for magnetic separation in a suspension system, and therefore it does not require additional magnetic components as is the usual case. Consequently, the MnFe2O4―graphene system becomes a dual function photocatalyst. The significant enhancement in photoactivity under visible light irradiation can be ascribed to the reduction of gaphene oxide (GO), because the photogenerated electrons of MnFe2O4 can transfer easily from the conduction band to the reduced GO, effectively preventing a direct recombination of electrons and holes. Hydroxyl radicals play the role of main oxidant in the MnFe2O4―graphene system, and the radicals' oxidation reaction is obviously dominant. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476405
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012)[article] High photocatalytic activity of magnetically separable manganese ferrite – graphene heteroarchitectures [texte imprimé] / Yongsheng Fu, Auteur ; Pan Xiong, Auteur ; Haiqun Chen, Auteur . - 2012.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012)
Mots-clés : Photocatalysis Résumé : A simple and straightforward strategy was developed to fabricate magnetically separable MnFe2O4―grapbene photocatalysts with differing graphene content. It was found that graphene sheets were fully exfoliated and decorated with MnFe2O4 nanocrystals having an average diameter of 5.65 nm and a narrow particle size distribution. It is very interesting that, although MnFe2O4 alone is photocatalytically inactive under visible light irradiation, the combination of MnFe2O4 nanoparticles with gaphene sheets leads to high photocatalytic activity for the degradation ofmethylene blue under visible light irradiation. The strong magnetic property of MnFe2O4 nanoparticles can be used for magnetic separation in a suspension system, and therefore it does not require additional magnetic components as is the usual case. Consequently, the MnFe2O4―graphene system becomes a dual function photocatalyst. The significant enhancement in photoactivity under visible light irradiation can be ascribed to the reduction of gaphene oxide (GO), because the photogenerated electrons of MnFe2O4 can transfer easily from the conduction band to the reduced GO, effectively preventing a direct recombination of electrons and holes. Hydroxyl radicals play the role of main oxidant in the MnFe2O4―graphene system, and the radicals' oxidation reaction is obviously dominant. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476405 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Solvent free selective oxidation of styrene and benzyl alcohol to benzaldehyde over an eco - friendly and reusable catalyst, undecamolybdophosphate supported onto neutral alumina Type de document : texte imprimé Auteurs : Anjali Patel, Auteur ; Soyeb Pathan, Auteur Année de publication : 2012 Article en page(s) : pp. 732–740 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Catalyst Oxidation Résumé : Supported undecamolybdophosphate was synthesized and characterized by various physicochemical techniques and successfully used for solvent free oxidation of styrene and of benzyl alcohol to benzaldehyde. Influence of the reaction parameters (molar ratio of substrate to H2O2, amount of the catalyst, reaction time, and reaction temperature) were studied. The catalyst was reused three times without any significant loss in the catalytic activity. FT-IR, XRD, and DRS of regenerated catalyst indicated that the catalyst was undegraded and stable after the reaction. The novelty of the work lies in obtaining a single selective product, benzaldehyde, as well as a high TON for the same, under mild conditions. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476406
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 732–740[article] Solvent free selective oxidation of styrene and benzyl alcohol to benzaldehyde over an eco - friendly and reusable catalyst, undecamolybdophosphate supported onto neutral alumina [texte imprimé] / Anjali Patel, Auteur ; Soyeb Pathan, Auteur . - 2012 . - pp. 732–740.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 732–740
Mots-clés : Catalyst Oxidation Résumé : Supported undecamolybdophosphate was synthesized and characterized by various physicochemical techniques and successfully used for solvent free oxidation of styrene and of benzyl alcohol to benzaldehyde. Influence of the reaction parameters (molar ratio of substrate to H2O2, amount of the catalyst, reaction time, and reaction temperature) were studied. The catalyst was reused three times without any significant loss in the catalytic activity. FT-IR, XRD, and DRS of regenerated catalyst indicated that the catalyst was undegraded and stable after the reaction. The novelty of the work lies in obtaining a single selective product, benzaldehyde, as well as a high TON for the same, under mild conditions. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476406 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Thermogravimetry analysis of CO2 and H2O reduction from solar nanosized Zn powder for thermochemical fuel production Type de document : texte imprimé Auteurs : Stéphane Abanades, Auteur Année de publication : 2012 Article en page(s) : pp. 741–750 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Production Fuel Powder Carbon dioxide Thermogravimetry Résumé : This study addresses the thermochemical production of CO and H2 as high-value solar fuels from CO2 and H2O using reactive Zn nanoparticles. A two-step thermochemical cycle was considered: Zn-rich nanopowder was first synthesized from solar thermal ZnO dissociation in a high-temperature solar chemical reactor and the reduced material was then used as an oxygen carrier during the CO2 and H2O reduction reactions. The kinetics of CO2 and H2O reduction was investigated by thermogravimetry to demonstrate that the solar-produced nanopartides react efficiently with CO2 and H2O. Zn started to react from 513 K and almost complete Zn conversion (reaction extent over 95%) was achieved at 633―773 K in less than 5 min, thus confirming that the active Zn-rich nanopowder exhibits rapid fuel production kinetics during H2O and CO2 dissociation. The reaction mechanism was best described by a nucleation and growth model with an activation energy of 43 kJ/mol and an oxidant order of 0.8. The high reactivity of zinc was attributed to the specific solar synthesis route involving ZnO thermal dissociation and condensation of Zn vapor as nanoparticles. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476407
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 741–750[article] Thermogravimetry analysis of CO2 and H2O reduction from solar nanosized Zn powder for thermochemical fuel production [texte imprimé] / Stéphane Abanades, Auteur . - 2012 . - pp. 741–750.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 741–750
Mots-clés : Production Fuel Powder Carbon dioxide Thermogravimetry Résumé : This study addresses the thermochemical production of CO and H2 as high-value solar fuels from CO2 and H2O using reactive Zn nanoparticles. A two-step thermochemical cycle was considered: Zn-rich nanopowder was first synthesized from solar thermal ZnO dissociation in a high-temperature solar chemical reactor and the reduced material was then used as an oxygen carrier during the CO2 and H2O reduction reactions. The kinetics of CO2 and H2O reduction was investigated by thermogravimetry to demonstrate that the solar-produced nanopartides react efficiently with CO2 and H2O. Zn started to react from 513 K and almost complete Zn conversion (reaction extent over 95%) was achieved at 633―773 K in less than 5 min, thus confirming that the active Zn-rich nanopowder exhibits rapid fuel production kinetics during H2O and CO2 dissociation. The reaction mechanism was best described by a nucleation and growth model with an activation energy of 43 kJ/mol and an oxidant order of 0.8. The high reactivity of zinc was attributed to the specific solar synthesis route involving ZnO thermal dissociation and condensation of Zn vapor as nanoparticles. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476407 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Study on ester - amide exchange reaction between PBS and PA6lcoT Type de document : texte imprimé Auteurs : Zhen Yao, Auteur ; Jia-ming Sun, Auteur ; Qiang Wang, Auteur Année de publication : 2012 Article en page(s) : pp. 751-757 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Exchange reaction Résumé : To improve the thermal properties and mechanical properties of synthetic biodegradable polymers, poly(butylene succinate) (PBS) and poly(hexamethylene isophthalamide-co-terephthalamide) (PA6IcoT) are reactively blended in a LIST corotating processor under melting conditions. The products are fractionated into insoluble and soluble parts using chloroform as the solvent. The Fourier transform infrared spectra of these two fractions confirm that the exchange reaction between PA6IcoT and PBS occurs when p-toluenesulfonic acid is used as the catalyst. On the basis of the 13C NMR analysis, the pathway of the exchange reaction is described. The extent of exchange reaction, average length of the various sequences, and degree of randomness in the reactive blends are calculated. It has been found that the randomness of copolymers is increased with the increase in reaction extent. Scanning electron microscopy (SEM) is employed to investigate morphology development of the reactive blends. It shows that the copolymers generated by the exchange reaction act as the compatibilizer to improve the compatibility of PBS and PA6IcoT. The fraction of PA6IcoT- and PBS-rich phases is significantly reduced with increasing reaction extent. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476408
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 751-757[article] Study on ester - amide exchange reaction between PBS and PA6lcoT [texte imprimé] / Zhen Yao, Auteur ; Jia-ming Sun, Auteur ; Qiang Wang, Auteur . - 2012 . - pp. 751-757.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 751-757
Mots-clés : Exchange reaction Résumé : To improve the thermal properties and mechanical properties of synthetic biodegradable polymers, poly(butylene succinate) (PBS) and poly(hexamethylene isophthalamide-co-terephthalamide) (PA6IcoT) are reactively blended in a LIST corotating processor under melting conditions. The products are fractionated into insoluble and soluble parts using chloroform as the solvent. The Fourier transform infrared spectra of these two fractions confirm that the exchange reaction between PA6IcoT and PBS occurs when p-toluenesulfonic acid is used as the catalyst. On the basis of the 13C NMR analysis, the pathway of the exchange reaction is described. The extent of exchange reaction, average length of the various sequences, and degree of randomness in the reactive blends are calculated. It has been found that the randomness of copolymers is increased with the increase in reaction extent. Scanning electron microscopy (SEM) is employed to investigate morphology development of the reactive blends. It shows that the copolymers generated by the exchange reaction act as the compatibilizer to improve the compatibility of PBS and PA6IcoT. The fraction of PA6IcoT- and PBS-rich phases is significantly reduced with increasing reaction extent. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476408 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Modeling the volumetric properties of ionic liquids using modified perturbed hard - sphere equation of state : Application to pure and binary mixtures Type de document : texte imprimé Auteurs : Hosseini, S. M., Auteur ; J. Moghadasi, Auteur ; M. M. Papari, Auteur Année de publication : 2012 Article en page(s) : pp. 758-766 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Thermodynamic properties Binary mixture Equations of state Ionic liquid Modeling Résumé : In this paper, an alternative corresponding states correlation was applied to the perturbed hard-sphere equation of state (PHS EOS) to improve the predictive power of this EOS for modeling the volumetric properties of ionic liquids (ILs) and their mixtures. Two temperature-dependent parameters appearing in the EOS have been determined using two reliable scaling constants, the surface tension and the liquid density, both at room temperature. The predictive power of the proposed model has been assessed by comparing the results with 2366 experimental data points over a broad range of pressores and temperatures. The overall average absolute deviation (AAD) of the calculated densities from literature data was found to be 0.77%. Generally, this work shows that the PHS EOS based on the surface tension property of ILs outperforms the PHS EOS based on critical properties. Moreover, the improved PHS EOS has been applied to predict the volumetric properties of 16 binary mixtures involving ILs. The second partners of binary mixtures studied in this work are water, ethanol, methanol, acetone, acetonitrile, propylene carbonate, and I-propanol. Furthermore, the binary mixtures of ILs have also been studied. From 1685 data points examined for the aforementioned binary mixtures, the AAD of the calculated densities and the excess volumes from those reported in the literature were found to be 0.38 and 0.56%, respectively. Finally, the nonadditivity behavior of the studied mixtures is also investigated. The sign of the nonadditivity parameter indicates a tendency toward attraction between the unlike molecules in the mixture. However, the value of this parameter is not large, which implies that the hard-sphere model is able to model the excess properties of the present mixtures. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476409
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 758-766[article] Modeling the volumetric properties of ionic liquids using modified perturbed hard - sphere equation of state : Application to pure and binary mixtures [texte imprimé] / Hosseini, S. M., Auteur ; J. Moghadasi, Auteur ; M. M. Papari, Auteur . - 2012 . - pp. 758-766.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 758-766
Mots-clés : Thermodynamic properties Binary mixture Equations of state Ionic liquid Modeling Résumé : In this paper, an alternative corresponding states correlation was applied to the perturbed hard-sphere equation of state (PHS EOS) to improve the predictive power of this EOS for modeling the volumetric properties of ionic liquids (ILs) and their mixtures. Two temperature-dependent parameters appearing in the EOS have been determined using two reliable scaling constants, the surface tension and the liquid density, both at room temperature. The predictive power of the proposed model has been assessed by comparing the results with 2366 experimental data points over a broad range of pressores and temperatures. The overall average absolute deviation (AAD) of the calculated densities from literature data was found to be 0.77%. Generally, this work shows that the PHS EOS based on the surface tension property of ILs outperforms the PHS EOS based on critical properties. Moreover, the improved PHS EOS has been applied to predict the volumetric properties of 16 binary mixtures involving ILs. The second partners of binary mixtures studied in this work are water, ethanol, methanol, acetone, acetonitrile, propylene carbonate, and I-propanol. Furthermore, the binary mixtures of ILs have also been studied. From 1685 data points examined for the aforementioned binary mixtures, the AAD of the calculated densities and the excess volumes from those reported in the literature were found to be 0.38 and 0.56%, respectively. Finally, the nonadditivity behavior of the studied mixtures is also investigated. The sign of the nonadditivity parameter indicates a tendency toward attraction between the unlike molecules in the mixture. However, the value of this parameter is not large, which implies that the hard-sphere model is able to model the excess properties of the present mixtures. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476409 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Synthesis and characterization of acicular iron oxide particles obtained from acid mine drainage and their catalytic properties in toluene oxidation Type de document : texte imprimé Auteurs : Silvia L. F. Andersen, Auteur ; Rubia G. Flores, Auteur ; Vivian S. Madeira, Auteur Année de publication : 2012 Article en page(s) : pp. 767-774 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Oxidation Catalytic reaction Acid mine drainage Résumé : Acid mine drainage (AMD) has long been a significant environmental problem resulting from the microbial oxidation of iron pyrite in the presence of water and air. This Article describe a method to produce acicular goethite particles (AGNs) from AMD and their application as a catalyst for the combustion of volatile organic compounds. Ferric ions were recovered from AMD as AGNs with relatively high purity via an oxidation-selective precipitation process during AMD treatment. Hematite materials (PNs) were produced when the AGNs were treated at 450 °C. These materials were characterized by XRD, SEM, TGA, and N2 adsorption/desorption. The PNs were tested as a combustion catalyst and shown to be useful for the oxidation of toluene. AGNs impregnated with manganese were used to prepare the PN_Mn5 catalyst. The catalysts selectively produced CO2 and water, representing a good alternative to commercially available catalysts in terms of origin and availability. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476410
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 767-774[article] Synthesis and characterization of acicular iron oxide particles obtained from acid mine drainage and their catalytic properties in toluene oxidation [texte imprimé] / Silvia L. F. Andersen, Auteur ; Rubia G. Flores, Auteur ; Vivian S. Madeira, Auteur . - 2012 . - pp. 767-774.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 767-774
Mots-clés : Oxidation Catalytic reaction Acid mine drainage Résumé : Acid mine drainage (AMD) has long been a significant environmental problem resulting from the microbial oxidation of iron pyrite in the presence of water and air. This Article describe a method to produce acicular goethite particles (AGNs) from AMD and their application as a catalyst for the combustion of volatile organic compounds. Ferric ions were recovered from AMD as AGNs with relatively high purity via an oxidation-selective precipitation process during AMD treatment. Hematite materials (PNs) were produced when the AGNs were treated at 450 °C. These materials were characterized by XRD, SEM, TGA, and N2 adsorption/desorption. The PNs were tested as a combustion catalyst and shown to be useful for the oxidation of toluene. AGNs impregnated with manganese were used to prepare the PN_Mn5 catalyst. The catalysts selectively produced CO2 and water, representing a good alternative to commercially available catalysts in terms of origin and availability. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476410 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Red mud from brazil : Thermal behavior and physical properties Type de document : texte imprimé Auteurs : Maria Lúcia Pereira Antunes, Auteur ; Sara Jane Couperthwaite, Auteur ; Fabiano Tomazini Da Conceiçao, Auteur Année de publication : 2012 Article en page(s) : pp. 775–779 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Thermal behavior Résumé : The main constituents of red mud produced in Aluminio city (S.P., Brazil) are iron, aluminum, and silicon oxides. It has been determined that the average particle diameter for this red mud is between 0.05 and 0.002 mm. It is observed that a decrease in the percentage of smaller particles occurs at temperatures greater than 400 °C. This observation corresponds with the thermal analysis and X-ray diffraction (XRD) data, which illustrate the phase transition of goethite to hematite. A 10% mass loss is observed in the thermal analysis patterns due to the hydroxide–oxide phase transitions of iron (primary phase transition) and aluminum (to a lesser extent). The disappearance and appearance of the different phases of iron and aluminum confirms the decomposition reactions proposed by the thermal analysis data. This Brazilian red mud has been classified as mesoporous at all temperatures except between 400 and 500 °C where the classification changes to micro/mesoporous. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201700k
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 775–779[article] Red mud from brazil : Thermal behavior and physical properties [texte imprimé] / Maria Lúcia Pereira Antunes, Auteur ; Sara Jane Couperthwaite, Auteur ; Fabiano Tomazini Da Conceiçao, Auteur . - 2012 . - pp. 775–779.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 775–779
Mots-clés : Thermal behavior Résumé : The main constituents of red mud produced in Aluminio city (S.P., Brazil) are iron, aluminum, and silicon oxides. It has been determined that the average particle diameter for this red mud is between 0.05 and 0.002 mm. It is observed that a decrease in the percentage of smaller particles occurs at temperatures greater than 400 °C. This observation corresponds with the thermal analysis and X-ray diffraction (XRD) data, which illustrate the phase transition of goethite to hematite. A 10% mass loss is observed in the thermal analysis patterns due to the hydroxide–oxide phase transitions of iron (primary phase transition) and aluminum (to a lesser extent). The disappearance and appearance of the different phases of iron and aluminum confirms the decomposition reactions proposed by the thermal analysis data. This Brazilian red mud has been classified as mesoporous at all temperatures except between 400 and 500 °C where the classification changes to micro/mesoporous. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201700k Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Schinopsis iorentzii extract as a green corrosion inhibitor for low carbon steel in 1 M HCl solution Type de document : texte imprimé Auteurs : Husnu Gerengi, Auteur ; Halil Ibrahim Sahin, Auteur Année de publication : 2012 Article en page(s) : pp. 780-787 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Carbon steel Corrosion inhibitor Extract Résumé : The corrosion inhibition of low carbon steel in 1 M HCl solution with different concentrations of Schinopsis lorentzii extract was studied using Tafel extrapolation, linear polarization, and electrochemical impedance spectroscopy (EIS). It was found that Schinopsis lorentzii extract acted as slightly cathodic inhibitor and inhibition efficiencies increased with the increase of extract concentration. The adsorption of the molecules of the extract on the low carbon steel surface was in accordance with the Temkin adsorption isotherm. The results showed that Schinopsis lorentzii extract could serve as a corrosion inhibitor of the low carbon steel in hydrochloric acid environment. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476412
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 780-787[article] Schinopsis iorentzii extract as a green corrosion inhibitor for low carbon steel in 1 M HCl solution [texte imprimé] / Husnu Gerengi, Auteur ; Halil Ibrahim Sahin, Auteur . - 2012 . - pp. 780-787.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 780-787
Mots-clés : Carbon steel Corrosion inhibitor Extract Résumé : The corrosion inhibition of low carbon steel in 1 M HCl solution with different concentrations of Schinopsis lorentzii extract was studied using Tafel extrapolation, linear polarization, and electrochemical impedance spectroscopy (EIS). It was found that Schinopsis lorentzii extract acted as slightly cathodic inhibitor and inhibition efficiencies increased with the increase of extract concentration. The adsorption of the molecules of the extract on the low carbon steel surface was in accordance with the Temkin adsorption isotherm. The results showed that Schinopsis lorentzii extract could serve as a corrosion inhibitor of the low carbon steel in hydrochloric acid environment. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476412 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Enhanced wet - chemical etching to prepare patterned silicon mask with controlled depths by combining photolithography with galvanic reaction Type de document : texte imprimé Auteurs : Nannan Sun, Auteur ; Jianming Chen, Auteur ; Chao Jiang, Auteur Année de publication : 2012 Article en page(s) : pp. 788-794 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Chemical etching Résumé : We have developed an enhanced wet-chemical method to prepare patterned silicon templates with controlled depths at microscale by combining photolithography with electroless metal etching. The silicon masks are obtained in the following procedures: patterned silicon wafers selectively etch through galvanic reactions and result in patterned surfaces with silicon nanoarrays in exposed areas during photolithography; the as-etched silicon wafers are corroded in a mixture etching solution to remove silicon nanoarrays, leading to patterned silicon templates. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476413
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 788-794[article] Enhanced wet - chemical etching to prepare patterned silicon mask with controlled depths by combining photolithography with galvanic reaction [texte imprimé] / Nannan Sun, Auteur ; Jianming Chen, Auteur ; Chao Jiang, Auteur . - 2012 . - pp. 788-794.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 788-794
Mots-clés : Chemical etching Résumé : We have developed an enhanced wet-chemical method to prepare patterned silicon templates with controlled depths at microscale by combining photolithography with electroless metal etching. The silicon masks are obtained in the following procedures: patterned silicon wafers selectively etch through galvanic reactions and result in patterned surfaces with silicon nanoarrays in exposed areas during photolithography; the as-etched silicon wafers are corroded in a mixture etching solution to remove silicon nanoarrays, leading to patterned silicon templates. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476413 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Coalescence of bubbles in aqueous alcohol solutions Type de document : texte imprimé Auteurs : Ayanavilli Srinivas, Auteur ; Pallab Ghosh, Auteur Année de publication : 2012 Article en page(s) : pp. 4824-4837 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Foam Modeling Prediction Stochastic model Stability Hydration Micellar critical concentration Surface tension Gas liquid interface Air water Adsorption Alcoholic solution Surfactant Aliphatic compound Non ionic surfactant Aqueous Bubble Coalescence Résumé : Coalescence of air bubbles in aqueous solutions of two aliphatic alcohols (viz. butanol and hexanol) and four nonionic surfactants (viz. Tween 20, Tween 40, Tween 60 and Tween 80) is reported in this work. Single-component alcohol and surfactant solutions as well as mixed binary surfactant-alcohol solutions were studied. Adsorption of the surface active compounds at air-water interface was studied by measuring the surface tension of the aqueous solutions. The critical micelle concentration and surface tension at this concentration were determined for the single and mixed surfactant-alcohol systems. The effect of concentration of surface active compounds on coalescence of air bubbles at flat air-water interface was studied. The role of electrostatic double layer, hydration and steric forces on coalescence was investigated. It was found that the stability of the thin aqueous films in mixed surfactant-alcohol systems depends on the subtle interplay of the intermolecular and surface forces in the film, which vary with the composition of the monolayer at the air-water interface. Stochastic distributions of coalescence time were observed in all systems. The coalescence time distributions were fitted by the stochastic model. The mean values of the distributions were compared with the predictions of seven film-drainage models. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24493381
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 4824-4837[article] Coalescence of bubbles in aqueous alcohol solutions [texte imprimé] / Ayanavilli Srinivas, Auteur ; Pallab Ghosh, Auteur . - 2012 . - pp. 4824-4837.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 4824-4837
Mots-clés : Foam Modeling Prediction Stochastic model Stability Hydration Micellar critical concentration Surface tension Gas liquid interface Air water Adsorption Alcoholic solution Surfactant Aliphatic compound Non ionic surfactant Aqueous Bubble Coalescence Résumé : Coalescence of air bubbles in aqueous solutions of two aliphatic alcohols (viz. butanol and hexanol) and four nonionic surfactants (viz. Tween 20, Tween 40, Tween 60 and Tween 80) is reported in this work. Single-component alcohol and surfactant solutions as well as mixed binary surfactant-alcohol solutions were studied. Adsorption of the surface active compounds at air-water interface was studied by measuring the surface tension of the aqueous solutions. The critical micelle concentration and surface tension at this concentration were determined for the single and mixed surfactant-alcohol systems. The effect of concentration of surface active compounds on coalescence of air bubbles at flat air-water interface was studied. The role of electrostatic double layer, hydration and steric forces on coalescence was investigated. It was found that the stability of the thin aqueous films in mixed surfactant-alcohol systems depends on the subtle interplay of the intermolecular and surface forces in the film, which vary with the composition of the monolayer at the air-water interface. Stochastic distributions of coalescence time were observed in all systems. The coalescence time distributions were fitted by the stochastic model. The mean values of the distributions were compared with the predictions of seven film-drainage models. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24493381 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Electric relaxational effects induced by displacement current in dielectric materials Type de document : texte imprimé Auteurs : Jan Jadzyn, Auteur ; Jolanta Swiergiel, Auteur Année de publication : 2012 Article en page(s) : pp. 807-813 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Dielectric materials Résumé : An investigation was carried out on frequency behavior of the complex electric modulus, the impedance and the conductance, related to the displacement current resulting from the normal Brownian dynamics of relaxing molecular dipoles in dielectric materials. The experiment was performed for the liquid crystalline smectic A phase of n-octylcyanobiphenyl (8CB) in the frequency region of 200 kHz―50 MHz, where the single dielectric relaxation of the Debye-type occurs and, at the same time, the ionic conductivity in the compound is negligibly low (σDC ≈ 0). DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476415
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 807-813[article] Electric relaxational effects induced by displacement current in dielectric materials [texte imprimé] / Jan Jadzyn, Auteur ; Jolanta Swiergiel, Auteur . - 2012 . - pp. 807-813.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 807-813
Mots-clés : Dielectric materials Résumé : An investigation was carried out on frequency behavior of the complex electric modulus, the impedance and the conductance, related to the displacement current resulting from the normal Brownian dynamics of relaxing molecular dipoles in dielectric materials. The experiment was performed for the liquid crystalline smectic A phase of n-octylcyanobiphenyl (8CB) in the frequency region of 200 kHz―50 MHz, where the single dielectric relaxation of the Debye-type occurs and, at the same time, the ionic conductivity in the compound is negligibly low (σDC ≈ 0). DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476415 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Planning under Demand and Yield Uncertainties in an Oil Supply Chain Type de document : texte imprimé Auteurs : Kailiang Tong, Auteur ; Yiping Feng, Auteur Année de publication : 2012 Article en page(s) : pp. 814-834 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Uncertainty Planning Résumé : In this article, a stochastic programming approach for an optimal refinery planning problem under uncertainties is proposed. The nominal planning model is extended by means of conditional value-at-risk theory. Demand amount uncertainty and product yield fluctuation are taken into account simultaneously. The risk of customer dissatisfaction and inventory violation are considered as constraints according to the decision maker's risk tolerance. Sample average approximation approach is employed to test the robustness of the model and determine the suitable risk aversion value. A more accurate product yield distribution based upon a Markov chain is introduced and applied in this model. A problem with such endogenous uncertainty is solved using a heuristic iterative algorithm integrating stochastic programming and simulation framework. Also, the scenario number in the stochastic programming model is determined by a statistical analysis, which is a compromise of model accuracy and problem size. At the end of this article, a comprehensive analysis is presented to illustrate the effectiveness of the proposed model. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476416
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 814-834[article] Planning under Demand and Yield Uncertainties in an Oil Supply Chain [texte imprimé] / Kailiang Tong, Auteur ; Yiping Feng, Auteur . - 2012 . - pp. 814-834.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 814-834
Mots-clés : Uncertainty Planning Résumé : In this article, a stochastic programming approach for an optimal refinery planning problem under uncertainties is proposed. The nominal planning model is extended by means of conditional value-at-risk theory. Demand amount uncertainty and product yield fluctuation are taken into account simultaneously. The risk of customer dissatisfaction and inventory violation are considered as constraints according to the decision maker's risk tolerance. Sample average approximation approach is employed to test the robustness of the model and determine the suitable risk aversion value. A more accurate product yield distribution based upon a Markov chain is introduced and applied in this model. A problem with such endogenous uncertainty is solved using a heuristic iterative algorithm integrating stochastic programming and simulation framework. Also, the scenario number in the stochastic programming model is determined by a statistical analysis, which is a compromise of model accuracy and problem size. At the end of this article, a comprehensive analysis is presented to illustrate the effectiveness of the proposed model. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476416 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Optimal design of a rotating packed bed for VOC stripping from contaminated groundwater Type de document : texte imprimé Auteurs : Krishna Gudena, Auteur ; G.P. Rangaiah, Auteur ; S. Lakshminarayanan, Auteur Année de publication : 2012 Article en page(s) : pp. 835-847 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Water pollution Ground water Stripping Volatile organic compound Packed bed Optimal design Résumé : Groundwater pollution by volatile organic compounds (VOCs) is a serious environmental concern, and several techniques have been suggested and employed to strip off these harmful compounds. Since groundwater is classified as a distributed scale system, an efficient VOC stripping system should be portable and economically competitive. The focus of the current study is to remove trichloroethylene (TCE) from contaminated groundwater in a rotating packed bed (high gravity or HiGee). Although industrial applications of HiGee do exist, studies on optimal design of the same is scarce in the literature. The present study optimizes the design of an industrial-scale HiGee stripping process with conflicting objectives such as total annual cost (TAC) and total VOC removal under consideration. The synergy effect of heating and rotation is studied, and several inferences from this study are listed. Pareto-optimal solutions obtained provide a wide range of optimized design alternatives, one of which can be chosen and employed by the designers, as per their end needs. Component-wise power consumption, uncertainty analysis, and sensitivity analysis of the involved parameters and variables are also studied to provide further insights into the process. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476417
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 835-847[article] Optimal design of a rotating packed bed for VOC stripping from contaminated groundwater [texte imprimé] / Krishna Gudena, Auteur ; G.P. Rangaiah, Auteur ; S. Lakshminarayanan, Auteur . - 2012 . - pp. 835-847.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 835-847
Mots-clés : Water pollution Ground water Stripping Volatile organic compound Packed bed Optimal design Résumé : Groundwater pollution by volatile organic compounds (VOCs) is a serious environmental concern, and several techniques have been suggested and employed to strip off these harmful compounds. Since groundwater is classified as a distributed scale system, an efficient VOC stripping system should be portable and economically competitive. The focus of the current study is to remove trichloroethylene (TCE) from contaminated groundwater in a rotating packed bed (high gravity or HiGee). Although industrial applications of HiGee do exist, studies on optimal design of the same is scarce in the literature. The present study optimizes the design of an industrial-scale HiGee stripping process with conflicting objectives such as total annual cost (TAC) and total VOC removal under consideration. The synergy effect of heating and rotation is studied, and several inferences from this study are listed. Pareto-optimal solutions obtained provide a wide range of optimized design alternatives, one of which can be chosen and employed by the designers, as per their end needs. Component-wise power consumption, uncertainty analysis, and sensitivity analysis of the involved parameters and variables are also studied to provide further insights into the process. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476417 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Optimization of water systems with the consideration of pressure drop and pumping Type de document : texte imprimé Auteurs : Szu Wen Hung, Auteur ; Jin-Kuk Kim, Auteur Année de publication : 2012 Article en page(s) : pp.848–859 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Optimization Water Pressure Pumping Résumé : Novel automated design method has been developed to consider impacts of pressure drop and pumping arrangement in the water network in which water reuse is exploited to reduce freshwater consumption in process industries. A superstructure-based optimization framework has been developed to systematically consider all the key design issues simultaneously, including flow rate constraints, pressure-drop constraints, and other operational constraints, as well as to fully accommodate rigorous economic trade-off between freshwater cost, piping cost, and pumping cost. The proposed optimization study enables the identification of the optimal distribution of water within the network, together with the most appropriate location and capacity of pumps required for water systems. A robust and reliable solution strategy has been developed to effectively deal with computational difficulties associated with solving a mixed-integer nonlinear programming problem, with the aid of the effective application of physical insights gained from conceptual understanding of the design problem. The network complexity has been readily controlled by imposing design constraints in the optimization. Examples have been provided to prove the effectiveness of the design method developed in this paper and to demonstrate the importance of considering pressure drop constraints in practice. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201775y?mi=snxuk8&af=R&pageSize=20&searchT [...]
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp.848–859[article] Optimization of water systems with the consideration of pressure drop and pumping [texte imprimé] / Szu Wen Hung, Auteur ; Jin-Kuk Kim, Auteur . - 2012 . - pp.848–859.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp.848–859
Mots-clés : Optimization Water Pressure Pumping Résumé : Novel automated design method has been developed to consider impacts of pressure drop and pumping arrangement in the water network in which water reuse is exploited to reduce freshwater consumption in process industries. A superstructure-based optimization framework has been developed to systematically consider all the key design issues simultaneously, including flow rate constraints, pressure-drop constraints, and other operational constraints, as well as to fully accommodate rigorous economic trade-off between freshwater cost, piping cost, and pumping cost. The proposed optimization study enables the identification of the optimal distribution of water within the network, together with the most appropriate location and capacity of pumps required for water systems. A robust and reliable solution strategy has been developed to effectively deal with computational difficulties associated with solving a mixed-integer nonlinear programming problem, with the aid of the effective application of physical insights gained from conceptual understanding of the design problem. The network complexity has been readily controlled by imposing design constraints in the optimization. Examples have been provided to prove the effectiveness of the design method developed in this paper and to demonstrate the importance of considering pressure drop constraints in practice. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201775y?mi=snxuk8&af=R&pageSize=20&searchT [...] Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Optimal feed point design and regulation of a novel plate reactor Type de document : texte imprimé Auteurs : Yingying Chen, Auteur ; Karlene A. Hoo, Auteur Année de publication : 2012 Article en page(s) : pp. 860-871 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Reactor Regulation Design Résumé : This work uses an open-loop analysis of a novel plate reactor to determine the optimum number of feed points and their locations to achieve maximum conversion. Once the open-loop design is optimized, a control system is designed to achieve maximum conversion of the reactants by regulating the reactor temperature using discrete proportional-integral-derivative (PID) controllers. It was found that the optimum number of feed points is two, equidistantly spaced from each other, and also that a PID controller design based on the internal model control method gives the best closed-loop performance. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476419
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 860-871[article] Optimal feed point design and regulation of a novel plate reactor [texte imprimé] / Yingying Chen, Auteur ; Karlene A. Hoo, Auteur . - 2012 . - pp. 860-871.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 860-871
Mots-clés : Reactor Regulation Design Résumé : This work uses an open-loop analysis of a novel plate reactor to determine the optimum number of feed points and their locations to achieve maximum conversion. Once the open-loop design is optimized, a control system is designed to achieve maximum conversion of the reactants by regulating the reactor temperature using discrete proportional-integral-derivative (PID) controllers. It was found that the optimum number of feed points is two, equidistantly spaced from each other, and also that a PID controller design based on the internal model control method gives the best closed-loop performance. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476419 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Robust iterative learning control with quadratic performance index Type de document : texte imprimé Auteurs : Zuhua Xu, Auteur ; Jun Zhao, Auteur ; Yi Yang, Auteur Année de publication : 2012 Article en page(s) : pp. 872-881 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Learning Résumé : In this paper, a robust iterative learning control (ILC) designed through a linear matrix inequality (LMI) approach is proposed first, based on the worst-case performance index with ellipsoidal uncertainty and polytopic uncertainty, respectively. Since the design based on worst-case performance index is too conservative, a novel ILC design based on nominal performance index is further proposed, and its robust convergence properties are proven. The latter can give better performance when the nominal model is dose to the true process. Simulations have demonstrated the effectiveness and excellent performance of the proposed methods. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476420
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 872-881[article] Robust iterative learning control with quadratic performance index [texte imprimé] / Zuhua Xu, Auteur ; Jun Zhao, Auteur ; Yi Yang, Auteur . - 2012 . - pp. 872-881.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 872-881
Mots-clés : Learning Résumé : In this paper, a robust iterative learning control (ILC) designed through a linear matrix inequality (LMI) approach is proposed first, based on the worst-case performance index with ellipsoidal uncertainty and polytopic uncertainty, respectively. Since the design based on worst-case performance index is too conservative, a novel ILC design based on nominal performance index is further proposed, and its robust convergence properties are proven. The latter can give better performance when the nominal model is dose to the true process. Simulations have demonstrated the effectiveness and excellent performance of the proposed methods. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476420 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Experimental investigation of a novel polymeric heat exchanger using modified polypropylene hollow fibers Type de document : texte imprimé Auteurs : Yuchun Qin, Auteur ; Baoan Li, Auteur ; Shichang Wang, Auteur Année de publication : 2012 Article en page(s) : pp. 882-890 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Hollow fiber Heat exchanger Résumé : Plastic heat exchangers have attracted more and more attention because of their superior resistance to chemicals and fouling. However, the thermal conductivity of plastic materials is much lower than that of metal, which limits the wider application of plastic heat exchangers. In this study, polypropylene-based hollow fibers as a heat-conducting medium for heat exchangers was developed by melt-mixing polypropylene with graphite particles and maleated polypropylene (PP-g-MA). Results show that the addition of graphite fairly improved the crystalline, thermal stability and conductivity of the polypropylene resin and further improved the heat transfer efficienry of polypropylene-based hollow fiber heat exchangers. The overall heat transfer coefficient of 15.0 wt % graphite modified polypropylene hollow fiber heat exchangers reached 1228.7 W/(m2·K), which is 5 times higher than that of pure PP-based hollow fiber heat exchangers, and the overall conductance per unit volume reached 1.1 × 106 W/(m3·K). Further, the heat transfer efficiency increases fairly with the increase of the fluid flow rate, especially with the flow rate of the tube- side. The optimized operation mode is that the hot water flows on the tube-side and the cold water flows on the shell-side. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476421
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 882-890[article] Experimental investigation of a novel polymeric heat exchanger using modified polypropylene hollow fibers [texte imprimé] / Yuchun Qin, Auteur ; Baoan Li, Auteur ; Shichang Wang, Auteur . - 2012 . - pp. 882-890.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 882-890
Mots-clés : Hollow fiber Heat exchanger Résumé : Plastic heat exchangers have attracted more and more attention because of their superior resistance to chemicals and fouling. However, the thermal conductivity of plastic materials is much lower than that of metal, which limits the wider application of plastic heat exchangers. In this study, polypropylene-based hollow fibers as a heat-conducting medium for heat exchangers was developed by melt-mixing polypropylene with graphite particles and maleated polypropylene (PP-g-MA). Results show that the addition of graphite fairly improved the crystalline, thermal stability and conductivity of the polypropylene resin and further improved the heat transfer efficienry of polypropylene-based hollow fiber heat exchangers. The overall heat transfer coefficient of 15.0 wt % graphite modified polypropylene hollow fiber heat exchangers reached 1228.7 W/(m2·K), which is 5 times higher than that of pure PP-based hollow fiber heat exchangers, and the overall conductance per unit volume reached 1.1 × 106 W/(m3·K). Further, the heat transfer efficiency increases fairly with the increase of the fluid flow rate, especially with the flow rate of the tube- side. The optimized operation mode is that the hot water flows on the tube-side and the cold water flows on the shell-side. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476421 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : n - Propyl propionate synthesis via catalytic distillation - experimental investigation in pilot - scale Type de document : texte imprimé Auteurs : Carsten Buchaly, Auteur ; Peter Kreis, Auteur Année de publication : 2012 Article en page(s) : pp. 891-899 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Distillation Catalytic reaction Résumé : Catalytic distillation experiments were designed and carried out in a pilot-scale column to prove the technical feasibility of the heterogeneously catalyzed n-propyl propionate synthesis by esterification of propionic acid with 1-propanol using the surface-sulfonated ion-exchange resin Amberlyst 46. The experiments cover a broad range of decisive operational parameters, for example, reflux ratio, column load, distillate-to-feed ratio, and molar feed ratio of the reactants. The reconciled results comprise a complete set of concentration and temperature profiles along the column height and, hence, exhibit detailed and reliable data for model validation purposes. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476422
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 891-899[article] n - Propyl propionate synthesis via catalytic distillation - experimental investigation in pilot - scale [texte imprimé] / Carsten Buchaly, Auteur ; Peter Kreis, Auteur . - 2012 . - pp. 891-899.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 891-899
Mots-clés : Distillation Catalytic reaction Résumé : Catalytic distillation experiments were designed and carried out in a pilot-scale column to prove the technical feasibility of the heterogeneously catalyzed n-propyl propionate synthesis by esterification of propionic acid with 1-propanol using the surface-sulfonated ion-exchange resin Amberlyst 46. The experiments cover a broad range of decisive operational parameters, for example, reflux ratio, column load, distillate-to-feed ratio, and molar feed ratio of the reactants. The reconciled results comprise a complete set of concentration and temperature profiles along the column height and, hence, exhibit detailed and reliable data for model validation purposes. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476422 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Fluoride removal from water using bio - char, a green waste, low - cost adsorbent : Equilibrium uptake and sorption dynamics modeling Type de document : texte imprimé Auteurs : Dinesh Mohan, Auteur ; Rupa Sharma, Auteur ; Vinod K. Singh, Auteur Année de publication : 2012 Article en page(s) : pp. 900-914 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Modeling Dynamic model Sorption Uptake Résumé : Drinking water containing fluoride > 1 mg/L is unsafe for human consumption. Higher intake of fluoride can cause potential health hazards. Low-cost pine wood and pine bark chars, obtained as a byproduct from fast pyrolysis in an auger reactor at 400 and 450 °C, were characterized and used as received for water defluoridation. Sorption studies were performed at different temperatures, pH values, and solid to liquid ratios in the batch mode. Maximum fluoride adsorption occurred at pH 2.0. A kinetic study yielded an optimum equilibrium time of 48 h with an adsorbent dose of 10 g/L. Sorption isotherm studies were conducted over a concentration range of 1-100 mg/L. Fluoride adsorption decreased with an increase in temperature. The char performances were evaluated using the Freundlich, Langmuir, Redlich―Peterson, Toth, Temldn, Sips, and Radke adsorption models. Based on average percent error, the best isotherm fits follow the orders for pine wood and pine bark: PWLangmuir ≈ PWRedlich-Peterson > PWToth > PWSips > PWRadke-Prusnitz ≈ PWFreundlich > PWTemkin and PBToth > PBRadke-Prausnitz ≈PBFreundlich > PBRedlich-Peterson > PBLangmuir > PBSips > PBTemkin. The pine chars successfully treated fluoride-contaminated groundwater at pH 2.0. The chars swelled in water due to their high oxygen content (8―11%), opening new internal pore volume. Fluoride could also diffuse into portions of the chars'subsurface solid volume promoting further adsorption. Ion exchange and metal fluoride precipitation are modes of adsorption. Remarkably, these chars (SBET: 1―3 m2g―1) can remove similar amounts or more fluoride than activated carbon (SBET: ∼1000 m2g―1). DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476423
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 900-914[article] Fluoride removal from water using bio - char, a green waste, low - cost adsorbent : Equilibrium uptake and sorption dynamics modeling [texte imprimé] / Dinesh Mohan, Auteur ; Rupa Sharma, Auteur ; Vinod K. Singh, Auteur . - 2012 . - pp. 900-914.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 900-914
Mots-clés : Modeling Dynamic model Sorption Uptake Résumé : Drinking water containing fluoride > 1 mg/L is unsafe for human consumption. Higher intake of fluoride can cause potential health hazards. Low-cost pine wood and pine bark chars, obtained as a byproduct from fast pyrolysis in an auger reactor at 400 and 450 °C, were characterized and used as received for water defluoridation. Sorption studies were performed at different temperatures, pH values, and solid to liquid ratios in the batch mode. Maximum fluoride adsorption occurred at pH 2.0. A kinetic study yielded an optimum equilibrium time of 48 h with an adsorbent dose of 10 g/L. Sorption isotherm studies were conducted over a concentration range of 1-100 mg/L. Fluoride adsorption decreased with an increase in temperature. The char performances were evaluated using the Freundlich, Langmuir, Redlich―Peterson, Toth, Temldn, Sips, and Radke adsorption models. Based on average percent error, the best isotherm fits follow the orders for pine wood and pine bark: PWLangmuir ≈ PWRedlich-Peterson > PWToth > PWSips > PWRadke-Prusnitz ≈ PWFreundlich > PWTemkin and PBToth > PBRadke-Prausnitz ≈PBFreundlich > PBRedlich-Peterson > PBLangmuir > PBSips > PBTemkin. The pine chars successfully treated fluoride-contaminated groundwater at pH 2.0. The chars swelled in water due to their high oxygen content (8―11%), opening new internal pore volume. Fluoride could also diffuse into portions of the chars'subsurface solid volume promoting further adsorption. Ion exchange and metal fluoride precipitation are modes of adsorption. Remarkably, these chars (SBET: 1―3 m2g―1) can remove similar amounts or more fluoride than activated carbon (SBET: ∼1000 m2g―1). DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476423 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Multiscale simulation and experimental study of novel SiC structured packings Type de document : texte imprimé Auteurs : Xingang Li, Auteur ; Guohua Gao, Auteur ; Luhong Zhang, Auteur Année de publication : 2012 Article en page(s) : pp. 915-924 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Ordered packing Résumé : Two SiC corrugated structured packings are developed: one being smooth plate and the other made of porous SiC foam. Accordingly, a macroscale three-dimensional (3D) geometric module of two corrugated sheets is introduced with a periodic boundary and a microscale computational geometry is gained from arrayed tetrakaidecahedrons. Single-phase modeling is carried out in the macro module to determine the dry pressure drops for the two types of packing. The results show that the porous SiC packing has a higher pressure drop than that of the smooth one. Two-phase flow for smooth packing is simulated with a VOF-like model provided by CFX in the macroscale geometry. It is found that openings in corrugated plates can improve the film distribution and mass-transfer efficiency. Microsimulation of two-phase flow in the porous SiC packing is performed, and the results prove that liquid can go inside the SiC foam and extend along the foam matrix with a velocity. Therefore, the porous foam can provide a larger effective gas―liquid interfacial area for mass transfer, which explains its larger theoretical plate number, compared to the smooth packing. Performance parameters including pressure drop and liquid holdup have been measured to validate the simulation method, while the distillation experiments have been carried out to study the mass-transfer efficiency of the novel SiC packings. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476424
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 915-924[article] Multiscale simulation and experimental study of novel SiC structured packings [texte imprimé] / Xingang Li, Auteur ; Guohua Gao, Auteur ; Luhong Zhang, Auteur . - 2012 . - pp. 915-924.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 915-924
Mots-clés : Ordered packing Résumé : Two SiC corrugated structured packings are developed: one being smooth plate and the other made of porous SiC foam. Accordingly, a macroscale three-dimensional (3D) geometric module of two corrugated sheets is introduced with a periodic boundary and a microscale computational geometry is gained from arrayed tetrakaidecahedrons. Single-phase modeling is carried out in the macro module to determine the dry pressure drops for the two types of packing. The results show that the porous SiC packing has a higher pressure drop than that of the smooth one. Two-phase flow for smooth packing is simulated with a VOF-like model provided by CFX in the macroscale geometry. It is found that openings in corrugated plates can improve the film distribution and mass-transfer efficiency. Microsimulation of two-phase flow in the porous SiC packing is performed, and the results prove that liquid can go inside the SiC foam and extend along the foam matrix with a velocity. Therefore, the porous foam can provide a larger effective gas―liquid interfacial area for mass transfer, which explains its larger theoretical plate number, compared to the smooth packing. Performance parameters including pressure drop and liquid holdup have been measured to validate the simulation method, while the distillation experiments have been carried out to study the mass-transfer efficiency of the novel SiC packings. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476424 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Solubility and diffusivity of N2O in aqueous 4 - (Diethylamino) - 2 - butanol solutions for use in postcombustion CO2 capture Type de document : texte imprimé Auteurs : Teerawat Sema, Auteur ; Mohamed Edali, Auteur ; Abdulaziz Naami, Auteur Année de publication : 2012 Article en page(s) : pp. 925-930 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Carbon dioxide Diffusion coefficient Solubility Résumé : In this work, the solubility and diffusivity of nitrous oxide (N2O) in aqueous 4-(diethylamino)-2-butanol (DEAB) solutions were measured. Solubility was measured in a stirred cell reactor over the temperature range of 298―343 K and concentration range of 0.68―3.77 M. On the other hand, diffusivity was measured in a laminar jet absorber over the temperature range of 298―318 K and concentration range of 1.0―2.5 M. An attempt was made to correlate the solubility data with well-known models (semiempirical model, Redlich―Kister equation, and polynomial model). It was observed that only the polynomial model correlated the solubility of N2O in aqueous DEAB solution satisfactorily with an AAD of 0.1%. Similarly, an attempt was made to correlate the diffusivity data with well-known models (semiempirical model and modified Stokes-Einstein model). The semiempirical model provided better predicted N2O diffusivity data compared with the experimental data with an AAD of 3.4%. These data can then be used to determine the physical solubility and physical diffusivity of carbon dioxide (CO2) in aqueous DEAB solutions using the "N2O analogy". DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476425
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 925-930[article] Solubility and diffusivity of N2O in aqueous 4 - (Diethylamino) - 2 - butanol solutions for use in postcombustion CO2 capture [texte imprimé] / Teerawat Sema, Auteur ; Mohamed Edali, Auteur ; Abdulaziz Naami, Auteur . - 2012 . - pp. 925-930.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 925-930
Mots-clés : Carbon dioxide Diffusion coefficient Solubility Résumé : In this work, the solubility and diffusivity of nitrous oxide (N2O) in aqueous 4-(diethylamino)-2-butanol (DEAB) solutions were measured. Solubility was measured in a stirred cell reactor over the temperature range of 298―343 K and concentration range of 0.68―3.77 M. On the other hand, diffusivity was measured in a laminar jet absorber over the temperature range of 298―318 K and concentration range of 1.0―2.5 M. An attempt was made to correlate the solubility data with well-known models (semiempirical model, Redlich―Kister equation, and polynomial model). It was observed that only the polynomial model correlated the solubility of N2O in aqueous DEAB solution satisfactorily with an AAD of 0.1%. Similarly, an attempt was made to correlate the diffusivity data with well-known models (semiempirical model and modified Stokes-Einstein model). The semiempirical model provided better predicted N2O diffusivity data compared with the experimental data with an AAD of 3.4%. These data can then be used to determine the physical solubility and physical diffusivity of carbon dioxide (CO2) in aqueous DEAB solutions using the "N2O analogy". DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476425 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Validation of Dividing-Wall Columns Based on Experimental Data and Dynamic Simulations : Pilot-Plant and Production-Scale Columns Type de document : texte imprimé Auteurs : Gerit Niggemann, Auteur ; Georg Fieg, Auteur Année de publication : 2012 Article en page(s) : pp. 931-943 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Modeling Production Pilot plant Dynamic model Résumé : Dividing-wall columns are a promising separation device in terms of energy efficiency because they are suitable for the complete separation of ternary mixtures. The increased application of this progressive technology is based on reduced capital and operating costs. Although several articles have already been published in the field of dividing-wall columns, reliable knowledge is still missing concerning the dynamics of this separation process. To bridge this gap, experimental data on the process dynamics of dividing-wall columns around a steady-state operating point are presented herein, together with extensive model validation of the transient behavior of dividing-wall columns. Furthermore, the process model was successfully compared with experimental data from a production-scale dividing-wall column, which emphasizes the validity of the model. Thus, the validated process model serves as a virtual plant and can be used to develop and test future process control structures. Moreover, the knowledge gained from this study will help to increase the acceptance of dividing-wall columns in industry. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476426
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 931-943[article] Validation of Dividing-Wall Columns Based on Experimental Data and Dynamic Simulations : Pilot-Plant and Production-Scale Columns [texte imprimé] / Gerit Niggemann, Auteur ; Georg Fieg, Auteur . - 2012 . - pp. 931-943.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 931-943
Mots-clés : Modeling Production Pilot plant Dynamic model Résumé : Dividing-wall columns are a promising separation device in terms of energy efficiency because they are suitable for the complete separation of ternary mixtures. The increased application of this progressive technology is based on reduced capital and operating costs. Although several articles have already been published in the field of dividing-wall columns, reliable knowledge is still missing concerning the dynamics of this separation process. To bridge this gap, experimental data on the process dynamics of dividing-wall columns around a steady-state operating point are presented herein, together with extensive model validation of the transient behavior of dividing-wall columns. Furthermore, the process model was successfully compared with experimental data from a production-scale dividing-wall column, which emphasizes the validity of the model. Thus, the validated process model serves as a virtual plant and can be used to develop and test future process control structures. Moreover, the knowledge gained from this study will help to increase the acceptance of dividing-wall columns in industry. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476426 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Organic – inorganic hybrid silica membranes with controlled silica network size for propylene / propane separation Type de document : texte imprimé Auteurs : Masakoto Kanezashi, Auteur ; Mitsuki Kawano, Auteur ; Tomohisa Yoshioka, Auteur Année de publication : 2012 Article en page(s) : pp. 944–953 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Hybrid silica membranes Résumé : Bis(triethoxysilyl)methane (BTESM), which consists of Si–C–Si bonds, was used as a membrane precursor to control the size of amorphous silica networks. The single gas permeation characteristics of hybrid silica membranes were examined to determine the effect of silica precursors on amorphous networks. Pore size distribution, as determined by single gas permeation, suggested that average pore size was in the following order: bis(triethoxysilyl)ethane (BTESE)-derived silica > BTESM-derived silica > tetraethoxysilane (TEOS)-derived silica, due to differences in the minimum units of the silica precursor. The high C3H6/C3H8 separation performance of BTESM-derived silica membranes in a wide temperature range (50–200 °C) can be due to the control of silica network size by the “spacer” method using a Si–C–Si unit. For example, a BTESM-derived silica membrane showed a high C3H6 permeance of 6.32 × 10–7 mol m–2 s–1 Pa–1 with a C3H6/C3H8 permeance ratio of 8.8 at 50 °C. The order of C3H6 and C3H8 permeances of BTESM-derived silica membranes was C3H6 > C3H8, independent of the number of sol coats and temperature (50–200 °C), although the kinetic diameter of C3H6 (dk = 0.45 nm) was reported to be larger than that of C3H8 (dk = 0.43 nm). For permeation of hydrocarbons through amorphous silica membranes, it is suggested that the kinetic diameter, which is a minimum equilibrium cross-sectional diameter, is not applicable for effective molecular size, probably because diffusivity depends not only on the minimum cross section but also on molecular length. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201606k
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 944–953[article] Organic – inorganic hybrid silica membranes with controlled silica network size for propylene / propane separation [texte imprimé] / Masakoto Kanezashi, Auteur ; Mitsuki Kawano, Auteur ; Tomohisa Yoshioka, Auteur . - 2012 . - pp. 944–953.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 944–953
Mots-clés : Hybrid silica membranes Résumé : Bis(triethoxysilyl)methane (BTESM), which consists of Si–C–Si bonds, was used as a membrane precursor to control the size of amorphous silica networks. The single gas permeation characteristics of hybrid silica membranes were examined to determine the effect of silica precursors on amorphous networks. Pore size distribution, as determined by single gas permeation, suggested that average pore size was in the following order: bis(triethoxysilyl)ethane (BTESE)-derived silica > BTESM-derived silica > tetraethoxysilane (TEOS)-derived silica, due to differences in the minimum units of the silica precursor. The high C3H6/C3H8 separation performance of BTESM-derived silica membranes in a wide temperature range (50–200 °C) can be due to the control of silica network size by the “spacer” method using a Si–C–Si unit. For example, a BTESM-derived silica membrane showed a high C3H6 permeance of 6.32 × 10–7 mol m–2 s–1 Pa–1 with a C3H6/C3H8 permeance ratio of 8.8 at 50 °C. The order of C3H6 and C3H8 permeances of BTESM-derived silica membranes was C3H6 > C3H8, independent of the number of sol coats and temperature (50–200 °C), although the kinetic diameter of C3H6 (dk = 0.45 nm) was reported to be larger than that of C3H8 (dk = 0.43 nm). For permeation of hydrocarbons through amorphous silica membranes, it is suggested that the kinetic diameter, which is a minimum equilibrium cross-sectional diameter, is not applicable for effective molecular size, probably because diffusivity depends not only on the minimum cross section but also on molecular length. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201606k Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Selective sulphide precipitation of heavy metals from acidic polymetallic aqueous solution by thioacetamide Type de document : texte imprimé Auteurs : Mahdi Gharabaghi, Auteur ; Mehdi Irannajad, Auteur ; Amir Reza Azadmehr, Auteur Année de publication : 2012 Article en page(s) : pp. 954-963 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Aqueous solution Heavy metal Résumé : The selective separation and recovery of copper, cadmium, zinc, and nickel from a polymetallic solution with sulphide precipitation using thioacetamide have been investigated. Selective metal sulphide precipitation was studied as a function of pH, contact time, and temperature. The results showed that it was possible to separate metals by accurately controlling the pH and temperature. Below pH 2.5, copper precipitation was complete. The cadmium, zinc, and nickel selective precipitations were performed at pH of 4, 5.5, and 7.5, respectively. Temperature also had important effects on the selective separation, and metals precipitation yields increased with increasing temperature. Thioacetamide hydrolysis kinetics and its activation energies in various conditions were calculated. The metal sulphide precipitates were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the results showed that the produced precipitates had high purity. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476428
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 954-963[article] Selective sulphide precipitation of heavy metals from acidic polymetallic aqueous solution by thioacetamide [texte imprimé] / Mahdi Gharabaghi, Auteur ; Mehdi Irannajad, Auteur ; Amir Reza Azadmehr, Auteur . - 2012 . - pp. 954-963.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 954-963
Mots-clés : Aqueous solution Heavy metal Résumé : The selective separation and recovery of copper, cadmium, zinc, and nickel from a polymetallic solution with sulphide precipitation using thioacetamide have been investigated. Selective metal sulphide precipitation was studied as a function of pH, contact time, and temperature. The results showed that it was possible to separate metals by accurately controlling the pH and temperature. Below pH 2.5, copper precipitation was complete. The cadmium, zinc, and nickel selective precipitations were performed at pH of 4, 5.5, and 7.5, respectively. Temperature also had important effects on the selective separation, and metals precipitation yields increased with increasing temperature. Thioacetamide hydrolysis kinetics and its activation energies in various conditions were calculated. The metal sulphide precipitates were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the results showed that the produced precipitates had high purity. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476428 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Equilibrium and kinetics of reactiveextraction of ibuprofen enantiomers from organic solution by hydroxypropyl - B - cyclodextrin Type de document : texte imprimé Auteurs : Kewen Tang, Auteur ; Jian Cai, Auteur ; Panliang Zhang, Auteur Année de publication : 2012 Article en page(s) : pp. 964-971 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Enantiomer Kinetics Résumé : This paper reports on the equilibrium and kinetics of the reactive extraction of hydrophobic ibuprofen (IBU) enantiomers from the organic phase to the aqueous phase by hydroxypropyl-β-cyclodextrin (HP-β-CD). The modeling and experimental data of extraction performance factors were investigated to obtain the optimal extraction conditions. The best conditions identified involve the use of an HP-β-CD concentration of 0.03 mol/L and pH value of 2.5 at 10 °C. The theory of extraction accompanied by chemical reactions was used to obtain the intrinsic kinetics of the extraction of IBU enantiomers by HP- β-CD. The effects of process parameters, including the agitation speed, interfacial area, initial concentration of IBU enantiomers, initial concentration of extractant, and pH value of aqueous phase, on the initial extraction rate were separately studied. The reactions are first order in IBU and second order in HP-β-CD with forward rate constants of 7.21 x 10―4 m6/(mol2·s) for S-LBU and 4.58 × 10―4 m6/(mol2·s) for R-IBU, respectively. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476429
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 964-971[article] Equilibrium and kinetics of reactiveextraction of ibuprofen enantiomers from organic solution by hydroxypropyl - B - cyclodextrin [texte imprimé] / Kewen Tang, Auteur ; Jian Cai, Auteur ; Panliang Zhang, Auteur . - 2012 . - pp. 964-971.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 964-971
Mots-clés : Enantiomer Kinetics Résumé : This paper reports on the equilibrium and kinetics of the reactive extraction of hydrophobic ibuprofen (IBU) enantiomers from the organic phase to the aqueous phase by hydroxypropyl-β-cyclodextrin (HP-β-CD). The modeling and experimental data of extraction performance factors were investigated to obtain the optimal extraction conditions. The best conditions identified involve the use of an HP-β-CD concentration of 0.03 mol/L and pH value of 2.5 at 10 °C. The theory of extraction accompanied by chemical reactions was used to obtain the intrinsic kinetics of the extraction of IBU enantiomers by HP- β-CD. The effects of process parameters, including the agitation speed, interfacial area, initial concentration of IBU enantiomers, initial concentration of extractant, and pH value of aqueous phase, on the initial extraction rate were separately studied. The reactions are first order in IBU and second order in HP-β-CD with forward rate constants of 7.21 x 10―4 m6/(mol2·s) for S-LBU and 4.58 × 10―4 m6/(mol2·s) for R-IBU, respectively. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476429 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Selective uptake by akaganeite (B - FeOOH) of phosphite from hypophosphite and phosphite solutions Type de document : texte imprimé Auteurs : Ramesh Chitrakar, Auteur ; Yoji Makita, Auteur ; Takahiro Hirotsu, Auteur Année de publication : 2012 Article en page(s) : pp. 972-977 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Uptake Résumé : The anion-exchange properties of akaganeite (β-FeOOH) with phosphite (H2PO3― and HPO32― ) are reported herein. Uptake of phosphite by akaganeite followed the Freundlich isotherm model with exchange capacity of 1.0 mmol/g, and high distribution coefficients in multianion solution of 2.0 mmol/dm3 concentration (7.0 x 103 cm3/g at pH 3.9). Akaganeite displayed nearly constant uptake of phosphite (0.9 mmol/g) at pH 2.5―6.0. The kinetics on uptake of phosphite rapidly reached an equilibrium in 4 h. Akaganeite was also found to be feasible for high uptake of phosphite (1.2 mmol/g) and low uptake of hypophosphite ( DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476430
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 972-977[article] Selective uptake by akaganeite (B - FeOOH) of phosphite from hypophosphite and phosphite solutions [texte imprimé] / Ramesh Chitrakar, Auteur ; Yoji Makita, Auteur ; Takahiro Hirotsu, Auteur . - 2012 . - pp. 972-977.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 972-977
Mots-clés : Uptake Résumé : The anion-exchange properties of akaganeite (β-FeOOH) with phosphite (H2PO3― and HPO32― ) are reported herein. Uptake of phosphite by akaganeite followed the Freundlich isotherm model with exchange capacity of 1.0 mmol/g, and high distribution coefficients in multianion solution of 2.0 mmol/dm3 concentration (7.0 x 103 cm3/g at pH 3.9). Akaganeite displayed nearly constant uptake of phosphite (0.9 mmol/g) at pH 2.5―6.0. The kinetics on uptake of phosphite rapidly reached an equilibrium in 4 h. Akaganeite was also found to be feasible for high uptake of phosphite (1.2 mmol/g) and low uptake of hypophosphite ( DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476430 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : PVDF / Nanosilica dual - layer hollow fibers with enhanced selectivity and flux as novel membranes for ethanol recovery Type de document : texte imprimé Auteurs : Panu Sukitpaneenit, Auteur ; Tai-Shung Chung, Auteur Année de publication : 2012 Article en page(s) : pp. 978–993 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Nanosilica Ethanol Résumé : In this work, we have demonstrated the design and engineering of poly(vinylidene fluoride) (PVDF)/nanosilica dual-layer hollow fibers as novel pervaporation membranes for ethanol recovery. The newly developed dual-layer hollow fiber membrane can exhibit a high separation factor of up to 29 with a sustainable high flux of 1.1 kg m–2 h–1, which is equivalent to the separation performance regime of inorganic membranes. Central to this performance achievement is the synergy of (1) desirable membrane morphology, nanopore size, and high surface porosity of a thin-PVDF/nanosilica composite on a fully porous substrate accomplished by the dual-layer coextrusion technology, and (2) optimal operating downstream pressure with the aid of controlled pervaporation transport. The membrane selectivity-downstream pressure dependence of PVDF/nanosilica hybrid membranes is comprehensible via a modified pore-flow model. This study may represent a new class of membranes for ethanol–water separation. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202116h
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 978–993[article] PVDF / Nanosilica dual - layer hollow fibers with enhanced selectivity and flux as novel membranes for ethanol recovery [texte imprimé] / Panu Sukitpaneenit, Auteur ; Tai-Shung Chung, Auteur . - 2012 . - pp. 978–993.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 978–993
Mots-clés : Nanosilica Ethanol Résumé : In this work, we have demonstrated the design and engineering of poly(vinylidene fluoride) (PVDF)/nanosilica dual-layer hollow fibers as novel pervaporation membranes for ethanol recovery. The newly developed dual-layer hollow fiber membrane can exhibit a high separation factor of up to 29 with a sustainable high flux of 1.1 kg m–2 h–1, which is equivalent to the separation performance regime of inorganic membranes. Central to this performance achievement is the synergy of (1) desirable membrane morphology, nanopore size, and high surface porosity of a thin-PVDF/nanosilica composite on a fully porous substrate accomplished by the dual-layer coextrusion technology, and (2) optimal operating downstream pressure with the aid of controlled pervaporation transport. The membrane selectivity-downstream pressure dependence of PVDF/nanosilica hybrid membranes is comprehensible via a modified pore-flow model. This study may represent a new class of membranes for ethanol–water separation. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202116h Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Characterization of the hydrodynamics and mixing performance of a split - and - recombination (SAR) prototype microreactor and a multilamination commercial microreactor Type de document : texte imprimé Auteurs : Lionel S. Méndez-Portillo, Auteur ; Louis Fradette, Auteur ; Charles Dubois, Auteur Année de publication : 2012 Article en page(s) : pp. 994-1005 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Microreactor Mixing Hydrodynamics Résumé : The aim of this work was to quantify the performance of two well-known mixing mechanisms used in microreactors: the split-and-recombination (SAR) and the multilamination by means of an interdigital structure. The residence time distribution (RTD) and the mixing performance in laminar flow regime were experimentally characterized by the tracer pulse-input technique and the iodide-iodate Villermaux/Dushman method. RTD analysis indicates bypassing caused by uneven flow distribution in the manifolds of both microreactors. A decrease of the quadratic dependence of axial dispersion on fluid velocity is produced by the improved tracer homogenization achieved in the microfluidic structures. The iodide-iodate method shows that below a critical Damköhler number the microreactors exhibit a superior mixing performance than a conventional T-junction. The interdigital microreactor displayed the best mixing capabilities for all the flow conditions investigated. However, the estimation of energy dissipation confirms that the improved mixing performance of the interdigital unit is obtained at the expense of greater energy expenditure when compared with the split-and-recombination microreactor. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476432
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 994-1005[article] Characterization of the hydrodynamics and mixing performance of a split - and - recombination (SAR) prototype microreactor and a multilamination commercial microreactor [texte imprimé] / Lionel S. Méndez-Portillo, Auteur ; Louis Fradette, Auteur ; Charles Dubois, Auteur . - 2012 . - pp. 994-1005.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 994-1005
Mots-clés : Microreactor Mixing Hydrodynamics Résumé : The aim of this work was to quantify the performance of two well-known mixing mechanisms used in microreactors: the split-and-recombination (SAR) and the multilamination by means of an interdigital structure. The residence time distribution (RTD) and the mixing performance in laminar flow regime were experimentally characterized by the tracer pulse-input technique and the iodide-iodate Villermaux/Dushman method. RTD analysis indicates bypassing caused by uneven flow distribution in the manifolds of both microreactors. A decrease of the quadratic dependence of axial dispersion on fluid velocity is produced by the improved tracer homogenization achieved in the microfluidic structures. The iodide-iodate method shows that below a critical Damköhler number the microreactors exhibit a superior mixing performance than a conventional T-junction. The interdigital microreactor displayed the best mixing capabilities for all the flow conditions investigated. However, the estimation of energy dissipation confirms that the improved mixing performance of the interdigital unit is obtained at the expense of greater energy expenditure when compared with the split-and-recombination microreactor. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476432 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Solution of the span – wagner equation of state using a density – energy state function for fluid - dynamic simulation of carbon dioxide Type de document : texte imprimé Auteurs : Knut Erik Teigen Giljarhus, Auteur ; Svend Tollak Munkejord, Auteur ; Geir Skaugen, Auteur Année de publication : 2012 Article en page(s) : pp. 1006–1014 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Fluid dynamic Carbon Dioxide Résumé : With the introduction of carbon capture and storage (CCS) as a means to reduce carbon emissions, a need has arisen for accurate and efficient simulation tools. In this work, we propose a method for dynamic simulations of carbon dioxide using the Span–Wagner reference equation of state. The simulations are based on using the density and internal energy as states, which is a formulation naturally resulting from mass and energy balances. The proposed numerical method uses information about saturation lines to choose between single-phase and two-phase equation systems, and is capable of handling phase transitions. To illustrate the potential of the method, it is applied to simulations of tank depressurization, and to fluid-dynamic simulations of pipe transport. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201748a
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1006–1014[article] Solution of the span – wagner equation of state using a density – energy state function for fluid - dynamic simulation of carbon dioxide [texte imprimé] / Knut Erik Teigen Giljarhus, Auteur ; Svend Tollak Munkejord, Auteur ; Geir Skaugen, Auteur . - 2012 . - pp. 1006–1014.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1006–1014
Mots-clés : Fluid dynamic Carbon Dioxide Résumé : With the introduction of carbon capture and storage (CCS) as a means to reduce carbon emissions, a need has arisen for accurate and efficient simulation tools. In this work, we propose a method for dynamic simulations of carbon dioxide using the Span–Wagner reference equation of state. The simulations are based on using the density and internal energy as states, which is a formulation naturally resulting from mass and energy balances. The proposed numerical method uses information about saturation lines to choose between single-phase and two-phase equation systems, and is capable of handling phase transitions. To illustrate the potential of the method, it is applied to simulations of tank depressurization, and to fluid-dynamic simulations of pipe transport. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201748a Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Liquid – liquid flow in a capillary microreactor : Hydrodynamic flow patterns and extraction performance Type de document : texte imprimé Auteurs : Jovan Jovanovic, Auteur ; Evgeny V. Rebrov, Auteur ; T. A. (Xander) Nijhuis, Auteur Année de publication : 2012 Article en page(s) : pp. 1015-1026 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Flow field Hydrodynamics Microreactor Liquid liquid flow Résumé : The capillary microreactor, with four stable operating flow patterns and a throughput range from grams per hour to kilograms per hour, presents an attractive alternative to chip-based and microstructured reactors for laboratory- and pilot-scale applications. In this article, results for the extraction of 2-butanol from toluene under different flow patterns in a water/toluene flow in long capillary microreactors are presented. The effects of the capillary length (0.4―2.2 m), flow rate (0.1-12 mL/min), and aqueous-to-organic volumetric flow ratio (0.25―9) on the slug, bubbly, parallel, and annular flow hydrodynamics were investigated. Weber-number-dependent flow maps were composed for capillary lengths of 0.4 and 2 m that were used to interpret the flow pattern formation in terms of surface tension and inertia forces. When the capillary length was decreased from 2 to 0.4 m, a transition from annular to parallel flow was observed. The capillary length had little influence on slug and bubbly flows. The flow patterns were evaluated in terms of stability, surface-to-volume ratio, throughput, and extraction efficiency. Slug and bubbly flow operations yielded 100% thermodynamic extraction efficiency, and increasing the aqueous-to-organic volumetric ratio to 9 allowed for 99% 2-butanol extraction. The parallel and annular flow operating windows were limited by the capillary length, thus yielding maximum 2-butanol extractions of 30% and 47% for parallel and annular flows, respectively. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476434
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1015-1026[article] Liquid – liquid flow in a capillary microreactor : Hydrodynamic flow patterns and extraction performance [texte imprimé] / Jovan Jovanovic, Auteur ; Evgeny V. Rebrov, Auteur ; T. A. (Xander) Nijhuis, Auteur . - 2012 . - pp. 1015-1026.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1015-1026
Mots-clés : Flow field Hydrodynamics Microreactor Liquid liquid flow Résumé : The capillary microreactor, with four stable operating flow patterns and a throughput range from grams per hour to kilograms per hour, presents an attractive alternative to chip-based and microstructured reactors for laboratory- and pilot-scale applications. In this article, results for the extraction of 2-butanol from toluene under different flow patterns in a water/toluene flow in long capillary microreactors are presented. The effects of the capillary length (0.4―2.2 m), flow rate (0.1-12 mL/min), and aqueous-to-organic volumetric flow ratio (0.25―9) on the slug, bubbly, parallel, and annular flow hydrodynamics were investigated. Weber-number-dependent flow maps were composed for capillary lengths of 0.4 and 2 m that were used to interpret the flow pattern formation in terms of surface tension and inertia forces. When the capillary length was decreased from 2 to 0.4 m, a transition from annular to parallel flow was observed. The capillary length had little influence on slug and bubbly flows. The flow patterns were evaluated in terms of stability, surface-to-volume ratio, throughput, and extraction efficiency. Slug and bubbly flow operations yielded 100% thermodynamic extraction efficiency, and increasing the aqueous-to-organic volumetric ratio to 9 allowed for 99% 2-butanol extraction. The parallel and annular flow operating windows were limited by the capillary length, thus yielding maximum 2-butanol extractions of 30% and 47% for parallel and annular flows, respectively. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476434 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Experimental and theoretical analysis of CO2 absorption in polyolester oil using the PC - SAFT equation of state to account for nonideal effects Type de document : texte imprimé Auteurs : Moisés A. Marcelino Neto, Auteur ; Jader R. Barbosa, Auteur Année de publication : 2012 Article en page(s) : pp. 1027-1035 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Thermodynamic properties Equations of state Gas absorption Carbon dioxide Résumé : The purpose of this work is to study the absorption of carbon dioxide (CO2) through the free surface of a stagnant layer of polyolester oil in a closed cell via the pressure decay method. The system pressure and local temperatures in the vapor and liquid phases were recorded as a function of time for system temperatures of 25, 40, 55, and 70 °C. The tests were carried out for two initial heights of the liquid layer of 37 and 74 mm, respectively. The mass of CO2 that entered the cell was measured for each test. The data were used to validate a transient mass diffusion model that accounts for the departure from the ideal behavior. The model uses the PC-SAFT equation of state and incorporates the following nonideal effects: (i) gas compressibility in the vapor, (ii) liquid phase swelling, (iii) concentration-dependent nonideal density behavior, (iv) nonideal phase equilibrium at the vapor―liquid interface, and (v) concentration-dependent mass diffusivity. Absorption rates were found to be strongly dependent on, and inversely proportional to, the system temperature. The absolute average errors of the absolute pressure prediction were lower than 4%. When the nonideal effects are ignored, the absolute average errors can be as large as 30%. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476435
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1027-1035[article] Experimental and theoretical analysis of CO2 absorption in polyolester oil using the PC - SAFT equation of state to account for nonideal effects [texte imprimé] / Moisés A. Marcelino Neto, Auteur ; Jader R. Barbosa, Auteur . - 2012 . - pp. 1027-1035.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1027-1035
Mots-clés : Thermodynamic properties Equations of state Gas absorption Carbon dioxide Résumé : The purpose of this work is to study the absorption of carbon dioxide (CO2) through the free surface of a stagnant layer of polyolester oil in a closed cell via the pressure decay method. The system pressure and local temperatures in the vapor and liquid phases were recorded as a function of time for system temperatures of 25, 40, 55, and 70 °C. The tests were carried out for two initial heights of the liquid layer of 37 and 74 mm, respectively. The mass of CO2 that entered the cell was measured for each test. The data were used to validate a transient mass diffusion model that accounts for the departure from the ideal behavior. The model uses the PC-SAFT equation of state and incorporates the following nonideal effects: (i) gas compressibility in the vapor, (ii) liquid phase swelling, (iii) concentration-dependent nonideal density behavior, (iv) nonideal phase equilibrium at the vapor―liquid interface, and (v) concentration-dependent mass diffusivity. Absorption rates were found to be strongly dependent on, and inversely proportional to, the system temperature. The absolute average errors of the absolute pressure prediction were lower than 4%. When the nonideal effects are ignored, the absolute average errors can be as large as 30%. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476435 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Biodiesel from zophobas morio larva oil : Process optimization and FAME characterization Type de document : texte imprimé Auteurs : D. Leung, Auteur ; Depo Yang, Auteur ; Zhuoxue Li, Auteur Année de publication : 2012 Article en page(s) : pp. 1036-1040 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Optimization Résumé : The advancement of biodiesel production emphasizes the finding of new, low-cost, and plentiful raw materials. Insects, as one of the most plentiful biological resources worldwide, could be potential candidates for biodiesel production. In this study, Zophobas morio (Coleoptera: Tenebrionidae) was evaluated as an insect feedstock, attempting to prove the feasibility of producing qualified biodiesel. The oil content in dried Z. morio larvae was found to be 33.80 wt %. Biodiesel from Z. morio larva oil was prepared by acid esterification followed by alkaline transesterification. The parameters of the reaction were optimized at 1.25 wt % potassium hydroxide catalyst, a 5:1 methanol to oil ratio, a reaction temperature of 50 °C, and a reaction time of 45 min. Under these conditions, the maximum fatty acid methyl ester yield was 92.35 wt %. The biodiesel obtained was verified to be in compliance with the ASTM D6751 standard. This study supports the use of Z. morio larva oil as a viable and valuable raw feedstock for biodiesel production and indicates the potential use of insects as feedstock for applications in energy production. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476436
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1036-1040[article] Biodiesel from zophobas morio larva oil : Process optimization and FAME characterization [texte imprimé] / D. Leung, Auteur ; Depo Yang, Auteur ; Zhuoxue Li, Auteur . - 2012 . - pp. 1036-1040.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1036-1040
Mots-clés : Optimization Résumé : The advancement of biodiesel production emphasizes the finding of new, low-cost, and plentiful raw materials. Insects, as one of the most plentiful biological resources worldwide, could be potential candidates for biodiesel production. In this study, Zophobas morio (Coleoptera: Tenebrionidae) was evaluated as an insect feedstock, attempting to prove the feasibility of producing qualified biodiesel. The oil content in dried Z. morio larvae was found to be 33.80 wt %. Biodiesel from Z. morio larva oil was prepared by acid esterification followed by alkaline transesterification. The parameters of the reaction were optimized at 1.25 wt % potassium hydroxide catalyst, a 5:1 methanol to oil ratio, a reaction temperature of 50 °C, and a reaction time of 45 min. Under these conditions, the maximum fatty acid methyl ester yield was 92.35 wt %. The biodiesel obtained was verified to be in compliance with the ASTM D6751 standard. This study supports the use of Z. morio larva oil as a viable and valuable raw feedstock for biodiesel production and indicates the potential use of insects as feedstock for applications in energy production. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476436 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Growth behavior of aragonite under the influence of magnetic field, temperature, and impurity Type de document : texte imprimé Auteurs : Steven S.S. Wang, Auteur ; Meng - Chun Chang, Auteur ; Huan - Chieh Chang, Auteur Année de publication : 2012 Article en page(s) : pp. 1041-1049 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Impurity Magnetic field Résumé : With and without magnetization, the growth rates of aragonite seeds were measured in a stirred-tank crystallizer in the presence of Fe2+ or Sr2+ acting as an impurity at two temperature levels, using the constant-composition technique. The concentration range of the impurity investigated was between 0 and 2 ppm, and the temperature settings were either 25 or 35 °C. The individual factors each had a distinct effect on the growth rate of aragonite, and the combined effects became complicated, especially in the presence of Sr2+, which changed the surface structure of the aragonite seed dramatically. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476437
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1041-1049[article] Growth behavior of aragonite under the influence of magnetic field, temperature, and impurity [texte imprimé] / Steven S.S. Wang, Auteur ; Meng - Chun Chang, Auteur ; Huan - Chieh Chang, Auteur . - 2012 . - pp. 1041-1049.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1041-1049
Mots-clés : Impurity Magnetic field Résumé : With and without magnetization, the growth rates of aragonite seeds were measured in a stirred-tank crystallizer in the presence of Fe2+ or Sr2+ acting as an impurity at two temperature levels, using the constant-composition technique. The concentration range of the impurity investigated was between 0 and 2 ppm, and the temperature settings were either 25 or 35 °C. The individual factors each had a distinct effect on the growth rate of aragonite, and the combined effects became complicated, especially in the presence of Sr2+, which changed the surface structure of the aragonite seed dramatically. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476437 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Discrete particle simulation of particle flow in a stirred mill : Effect of mill properties and geometry Type de document : texte imprimé Auteurs : C.T. Jayasundara, Auteur ; R.Y. Yang, Auteur ; A. B. Yu, Auteur Année de publication : 2012 Article en page(s) : pp. 1050-1061 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Solids flow Résumé : Particle flow in a stirred mill was modeled using discrete element method, focusing on the effect of mill properties and stirrer configurations, such as particle-wall friction, the size of disc holes, distance between stirrers, and stirrer shape, on the flow properties of grinding media. The flow properties were analyzed in terms ofvelocity field, porosity distribution, collision frequency, collision energy, impact energy, and power draw. The results indicate that although particle-wall sliding friction coefficient affects the energy transfer from discs to particles, too high a sliding friction may lead to a decrease in energy efficiency. The distance between discs significantly affects the circulation of grinding media between discs. Among the different stirrer types considered, energy transfer is more effective when disc holes are present. Pin stirrer shows increased grinding rates which also results in relatively high power consumption. Although different collision environments exist with different stirrer types, it is shown that the grinding rate can be determined by the first-order kinetics where the rate constant is dependent on the impact energy, for a given material. Grinding efficiency has been compared for different grinding materials under different operating conditions. The results suggest that selection of stirrer geometry also depends on the feed size and the type of material to be ground. Discussion has also been made of the usefulness of particle scale information in the design and control of stirred mills of different types. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476438
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1050-1061[article] Discrete particle simulation of particle flow in a stirred mill : Effect of mill properties and geometry [texte imprimé] / C.T. Jayasundara, Auteur ; R.Y. Yang, Auteur ; A. B. Yu, Auteur . - 2012 . - pp. 1050-1061.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1050-1061
Mots-clés : Solids flow Résumé : Particle flow in a stirred mill was modeled using discrete element method, focusing on the effect of mill properties and stirrer configurations, such as particle-wall friction, the size of disc holes, distance between stirrers, and stirrer shape, on the flow properties of grinding media. The flow properties were analyzed in terms ofvelocity field, porosity distribution, collision frequency, collision energy, impact energy, and power draw. The results indicate that although particle-wall sliding friction coefficient affects the energy transfer from discs to particles, too high a sliding friction may lead to a decrease in energy efficiency. The distance between discs significantly affects the circulation of grinding media between discs. Among the different stirrer types considered, energy transfer is more effective when disc holes are present. Pin stirrer shows increased grinding rates which also results in relatively high power consumption. Although different collision environments exist with different stirrer types, it is shown that the grinding rate can be determined by the first-order kinetics where the rate constant is dependent on the impact energy, for a given material. Grinding efficiency has been compared for different grinding materials under different operating conditions. The results suggest that selection of stirrer geometry also depends on the feed size and the type of material to be ground. Discussion has also been made of the usefulness of particle scale information in the design and control of stirred mills of different types. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476438 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Gas hydrate phase equilibrium in porous media : Mathematical modeling and correlation Type de document : texte imprimé Auteurs : Amir H. Mohammadi, Auteur ; Ali Eslamimanesh, Auteur ; Dominique Richon, Auteur Année de publication : 2012 Article en page(s) : pp. 1062-1072 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Correlation analysis Modeling Porous medium Phase equilibrium Gas hydrates Résumé : In this paper, we present two different approaches to represent/predict the gas hydrate phase equilibria for the carbon dioxide, methane, or ethane + pure water system in the presence of various types of porous media with different pore sizes. The studied porous media include silica gel, mesoporous silica, and porous silica glass. First, a correlation is presented, which estimates the hydrate suppression temperature due to the pore effects from the ice point depression (IPD). In the second place, several mathematical models are proposed using the least squares support vector machine (LSSVM) algorithm for the determination of the dissociation pressures of the corresponding systems. The results indicate that although the applied correlation based on the (IPD) leads to obtaining reliable results for the gas hydrate systems in the presence of porous silica glass media, the developed LSSVM models seem to be more general due to their predictive capability over all of the investigated systems. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476439
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1062-1072[article] Gas hydrate phase equilibrium in porous media : Mathematical modeling and correlation [texte imprimé] / Amir H. Mohammadi, Auteur ; Ali Eslamimanesh, Auteur ; Dominique Richon, Auteur . - 2012 . - pp. 1062-1072.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1062-1072
Mots-clés : Correlation analysis Modeling Porous medium Phase equilibrium Gas hydrates Résumé : In this paper, we present two different approaches to represent/predict the gas hydrate phase equilibria for the carbon dioxide, methane, or ethane + pure water system in the presence of various types of porous media with different pore sizes. The studied porous media include silica gel, mesoporous silica, and porous silica glass. First, a correlation is presented, which estimates the hydrate suppression temperature due to the pore effects from the ice point depression (IPD). In the second place, several mathematical models are proposed using the least squares support vector machine (LSSVM) algorithm for the determination of the dissociation pressures of the corresponding systems. The results indicate that although the applied correlation based on the (IPD) leads to obtaining reliable results for the gas hydrate systems in the presence of porous silica glass media, the developed LSSVM models seem to be more general due to their predictive capability over all of the investigated systems. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476439 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Multiphase CFD simulation of flow inside liquid seal drums of the refinery flare system Type de document : texte imprimé Auteurs : Randheer Yadav, Auteur ; Amitkumar Parekh, Auteur ; Ajay Gupta, Auteur Année de publication : 2012 Article en page(s) : pp. 1073-1082 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Refinery Drum Seal Computational fluid dynamics Résumé : The present work deals with improving the reliability of the liquid seal drum in the refinery flare system. CFD (based on volume of fluid concept) as well as theoretical modeling have been used for deciphering the hydrodynamics in two different designs (designated as design-1 and design-2) of the liquid seal drums. Results of the CFD simulations showed that the internals present in design-1 facilitate in bubble coalescing, thus resulting in large sized Taylor bubbles, which cause large fluctuations in the liquid level. Large level fluctuations create problems such as flare puffing, knocking, and dislodging of seal drum intemals. On the basis ofthe CFD model findings, a one-dimensional model based on Taylor bubble phenomenon1 has been adopted. Subsequently, the 1D model was used for calculating the Taylor bubble size and liquid level fluctuations. The 1D model was also used to predict the bubble size and liquid level fluctuation in another design (design-2) of the seal drum. Design-2 was also tested using CFD, which shows smooth passage of flare gas in the form of small bubbles with little fluctuation in liquid level On the basis of the study, it was suggested to change the design-1 by design-2. Suggestions were implemented in the plant, which relieved it of problems faced with design-1. This led to reliability improvement and substantial monetary benefits. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476440
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1073-1082[article] Multiphase CFD simulation of flow inside liquid seal drums of the refinery flare system [texte imprimé] / Randheer Yadav, Auteur ; Amitkumar Parekh, Auteur ; Ajay Gupta, Auteur . - 2012 . - pp. 1073-1082.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1073-1082
Mots-clés : Refinery Drum Seal Computational fluid dynamics Résumé : The present work deals with improving the reliability of the liquid seal drum in the refinery flare system. CFD (based on volume of fluid concept) as well as theoretical modeling have been used for deciphering the hydrodynamics in two different designs (designated as design-1 and design-2) of the liquid seal drums. Results of the CFD simulations showed that the internals present in design-1 facilitate in bubble coalescing, thus resulting in large sized Taylor bubbles, which cause large fluctuations in the liquid level. Large level fluctuations create problems such as flare puffing, knocking, and dislodging of seal drum intemals. On the basis ofthe CFD model findings, a one-dimensional model based on Taylor bubble phenomenon1 has been adopted. Subsequently, the 1D model was used for calculating the Taylor bubble size and liquid level fluctuations. The 1D model was also used to predict the bubble size and liquid level fluctuation in another design (design-2) of the seal drum. Design-2 was also tested using CFD, which shows smooth passage of flare gas in the form of small bubbles with little fluctuation in liquid level On the basis of the study, it was suggested to change the design-1 by design-2. Suggestions were implemented in the plant, which relieved it of problems faced with design-1. This led to reliability improvement and substantial monetary benefits. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476440 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Temperature - induced irreversible change of ZnO optical energy gap Type de document : texte imprimé Auteurs : Yan Huo, Auteur ; Yun Hang Hu, Auteur Année de publication : 2012 Article en page(s) : pp. 1083-1085 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Optical energy Résumé : It is generally recognized that the change of ZnO optical properties due to high-temperature treatment is reversible. However, herein, it is reported that high-temperature treatment in air caused an irreversible decrease in ZnO optical energy gap (Eg). The irreversible decrease in Eg was enhanced with increasing treatment temperature. Furthermore, it was found that the irreversible decrease in Eg can be attributed to the enlargement of ZnO crystal particles. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476441
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1083-1085[article] Temperature - induced irreversible change of ZnO optical energy gap [texte imprimé] / Yan Huo, Auteur ; Yun Hang Hu, Auteur . - 2012 . - pp. 1083-1085.
Chimie industrielle
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1083-1085
Mots-clés : Optical energy Résumé : It is generally recognized that the change of ZnO optical properties due to high-temperature treatment is reversible. However, herein, it is reported that high-temperature treatment in air caused an irreversible decrease in ZnO optical energy gap (Eg). The irreversible decrease in Eg was enhanced with increasing treatment temperature. Furthermore, it was found that the irreversible decrease in Eg can be attributed to the enlargement of ZnO crystal particles. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476441 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
